Personal protective equipment management system using optical patterns for equipment and safety monitoring

ABSTRACT

In general, techniques are described for a personal protective equipment (PPE) management system (PPEMS) that uses images of optical patterns embodied on articles of personal protective equipment (PPEs) to identify safety conditions that correspond to usage of the PPEs. In one example, an article of personal protective equipment (PPE) includes a first optical pattern embodied on a surface of the article of PPE; a second optical pattern embodied on the surface of the article of PPE, wherein a spatial relation between the first optical pattern and the second optical pattern is indicative of an operational status of the article of PPE.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage filing under 35 U.S.C. 371 ofPCT/IB2018/056981, filed Sep. 12, 2018, which claims the benefit of U.S.Provisional Application No. 62/564,101, filed Sep. 27, 2017, thedisclosure of which is incorporated by reference in its/their entiretyherein.

TECHNICAL FIELD

The present disclosure relates to the field of personal protectiveequipment. More specifically, the present disclosure relates to airrespiratory systems such as filtered air systems.

BACKGROUND

Personal protective equipment (PPE) may be used to protect a user (e.g.,a worker) from harm or injury from a variety of causes in a workenvironment. For example, fall protection equipment is important safetyequipment for workers operating at potentially harmful or even deadlyheights. To help ensure safety in the event of a fall, workers oftenwear safety harnesses connected to support structures with fallprotection equipment such as lanyards, energy absorbers, self-retractinglifelines (SRLs), descenders, and the like. As another example, whenworking in areas where there is known to be, or there is a potential ofthere being, dusts, fumes, gases or other contaminants that arepotentially hazardous or harmful to health, it is usual for a worker touse a respirator or a clean air supply source. While a large variety ofrespiratory devices are available, some commonly used devices includepowered air purifying respirators (PAPR) and a self-contained breathingapparatus (SCBA). Other PPE include those for hearing protection (earplugs, earmuffs), vision protection (safety spectacles, goggles, weldingmask or other face shields), head protection (e.g., visors, hard hats,or the like), and protective clothing.

SUMMARY

In general, techniques are described for a personal protective equipment(PPE) management system (PPEMS) that uses images of optical patternsembodied on articles of personal protective equipment (PPEs) to identifysafety conditions that correspond to usage of the PPEs. Personalprotective equipment may be used in a variety of workplace environmentsand different types of PPE may have corresponding positionalrequirements for active operation in such environments.

According to aspects of this disclosure, an article of personalprotective equipment (PPE) may have embodied thereon an optical patternin an orientation. The PPE may in some examples have a plurality ofoptical patterns embodied thereon, each of the optical patterns in acorresponding orientation. A spatial relation between the opticalpatterns embodied on a PPE indicates an operational status of the PPE.For instance, for some types of a PPE, a distance between the opticalpatterns indicates the operational status of the PPE. For some types ofPPE, a relative orientation between the respective orientations of theoptical patterns indicates the operational status of the PPE.

According to aspects of this disclosure, a PPE management system (PPEMS)obtains images that include images of PPEs, such PPEs as described aboveand located within a work environment. The PPEMS processes one or moreof the images to determine a spatial relation between the opticalpattern embodied on the PPE and another optical pattern shown in theimages. The other optical pattern may also be embodied on the PPE,another PPE or device, or elsewhere in the work environment. Based onthe spatial relation, the PPEMS determines whether a safety conditioncorresponding to the PPE is present and performs an operation based onthe presence or absence of the safety condition.

The techniques may provide one or more advantages. For example,identifying safety conditions using optical patterns in captured imagesof PPEs may be more versatile and widely applicable than using devicestied to the PPEs, such as sensors, locks, barriers, or other devices forindicating or ensuring an operational status of the PPE (e.g., open vs.closed) or for indicating an unsafe spatial relationship between a PPEand another apparatus. As another example, workers may be less able todefeat the safety techniques described herein. As a still furtherexample, the PPEMS applying techniques described herein may be able todetermine a safety condition for a PPE without requiring a communicationsession or channel with the PPE, unlike other systems that may rely onreceiving a communication signal from a PPE indicating an operationalstatus of the PPE. Furthermore, in some instances, the PPEMS may be ableto process a captured image that includes images of multiple PPEs andrespective optical patterns, which allows the PPEMS to concurrentlyprocess and identify potential safety for the multiple PPEs withouthaving to process communication signals from each of the PPEs.

In one aspect, the present disclosure includes a system comprising atleast one image capture device; an article of personal protectiveequipment (PPE) that includes a first optical pattern embodied on asurface of the article of PPE; a computing device communicativelycoupled to the at least one image capture device, wherein the computingdevice is configured to: receive, from the at least one image capturedevice, one or more images that includes the first optical pattern and asecond optical pattern; determine, based at least in part on the firstoptical pattern and the second optical pattern, a spatial relationbetween the first optical pattern and the second optical pattern;identify, based at least in part on the spatial relation between thefirst optical pattern and the second optical pattern, a safety conditionthat corresponds at least in part to the article of PPE; and perform atleast one operation based at least in part on the safety condition.

In one aspect, the present disclosure includes an article of personalprotective equipment (PPE) that includes a first optical patternembodied on a surface of the article of PPE; a second optical patternembodied on the surface of the article of PPE, wherein a spatialrelation between the first optical pattern and the second opticalpattern is indicative of an operational status of the article of PPE.

In one aspect, the present disclosure includes a pair of optical tagscomprising a first optical tag and a second optical tag, the firstoptical tag having a first optical pattern encoding a first identifierand the second optical tag having a second optical pattern encoding asecond identifier, wherein the first identifier and the secondidentifier indicate, to a personal protective equipment (PPE) managementsystem, that the first optical tag and the second optical tag are usableas a pair of optical tags for indicating an operational status of anarticle of PPE when at least the first optical tag is attached to thearticle of PPE.

In one aspect, the present disclosure includes a method comprisingreceiving, by a computing device from at least one image capture device,an image that includes a first optical pattern embodied on a surface ofan article of personal protective equipment (PPE) and also includes asecond optical pattern; determining, by the computing device based atleast in part on the first optical pattern and the second opticalpattern, a spatial relation between the first optical pattern and thesecond optical pattern; identifying, by the computing device based atleast in part on the spatial relation between the first optical patternand the second optical pattern, a safety condition that corresponds atleast in part to the article of PPE; and performing, by the computingdevice, at least one operation based at least in part on the safetycondition.

The details of one or more examples of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the disclosure will be apparent from thedescription and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an example system in whicharticles of personal protective equipment (PPEs) are monitored by apersonal protective equipment management system (PPEMS) in accordancewith various techniques of this disclosure.

FIG. 2 is a block diagram illustrating, in detail, an operatingperspective of the PPEMS shown in FIG. 1.

FIG. 3 is a block diagram illustrating, in detail, an example computingdevice for a PPEMS, according to techniques of this disclosure.

FIGS. 4A-4B depict an example of a PPE in an active and standbyposition, the PPE having optical patterns embodied thereon, according totechniques of this disclosure.

FIGS. 5A-5C depict an example of a PPE in active and standby positions,the PPE having optical patterns embodied thereon, according totechniques of this disclosure.

FIGS. 6A-6B depict an example of a PPE and a machine, each having anoptical pattern embodied thereon, according to techniques of thisdisclosure.

FIG. 7 is a flowchart illustrating an example mode of operation for apersonal protective equipment management system, according to techniquesdescribed in this disclosure.

FIGS. 8A and 8B illustrate cross-sectional views of portions of anoptical pattern formed on a retroreflective sheet, in accordance withtechniques of this disclosure.

FIG. 9 is a data structure, usable by a PPEMS, for identifying a safetycondition in accordance with techniques described herein.

FIG. 10 is a data structure, usable by a PPEMS, for identifying a safetycondition in accordance with techniques described herein.

FIG. 11 is an example of an encoding usable for an optical pattern forembodiment on an PPE, according to techniques of this disclosure.

FIG. 12 is a graph illustrating properties of example optical tags,according to techniques of this disclosure.

FIGS. 13A-13B are graphs illustrating properties of example opticaltags, according to techniques of this disclosure.

FIG. 14 is a table of properties of example optical tags, according totechniques of this disclosure.

It is to be understood that the embodiments may be utilized andstructural changes may be made without departing from the scope of theinvention. The figures are not necessarily to scale. Like numbers usedin the figures refer to like components. However, it will be understoodthat the use of a number to refer to a component in a given figure isnot intended to limit the component in another figure labeled with thesame number.

DETAILED DESCRIPTION

FIG. 1 is a block diagram illustrating an example computing system 2that includes a personal protective equipment management system (PPEMS)6 for managing personal protective equipment, according to techniquesdescribed in this disclosure. In general, PPEMS 6 may provide dataacquisition, monitoring, activity logging, reporting, predictiveanalytics, safety condition identification, and alert generation. Forexample, PPEMS 6 includes an underlying analytics and safety conditionidentification engine and alerting system in accordance with variousexamples described herein. In general, a safety event may refer toactivities of a user of personal protective equipment (PPE), a safetycondition of the PPE, or a hazardous environmental condition. Forexample, in the context of hearing, vision, or head protectionequipment, a safety condition may be such protection equipment being ina standby configuration. In the context of hazardous equipment, a safetycondition may be proximity of a worker to the hazardous equipment.

As further described below, PPEMS 6 may provide an integrated suite ofpersonal safety protective equipment management tools and implementsvarious techniques of this disclosure. That is, PPEMS 6 may provide anintegrated, end-to-end system for managing personal protectiveequipment, e.g., safety equipment, used by workers 10 within one or morephysical environments 8, which may be construction sites, mining ormanufacturing sites or any physical environment. The techniques of thisdisclosure may be realized within various parts of computing environment2.

As shown in the example of FIG. 1, system 2 represents a computingenvironment in which computing device(s) within a plurality of physicalenvironments 8A, 8B (collectively, environments 8) electronicallycommunicate with PPEMS 6 via one or more computer networks 4. Each ofphysical environment 8 represents a physical environment, such as a workenvironment, in which one or more individuals, such as workers 10,utilize personal protective equipment 13 while engaging in tasks oractivities within the respective environment.

In this example, environment 8A is shown as generally as having workers10, while environment 8B is shown in expanded form to provide a moredetailed example. In the example of FIG. 1, a plurality of workers10A-10N are shown as utilizing PPE 13A-13N. Although PPE 13 in theexample of FIG. 1 are illustrated as respirators, the techniquesdescribed herein apply to other types of PPE, such as those for hearingprotection, vision protection, and head protection, as well asprotective clothing, trauma protection, other PPE forassisted/protective respiration, and so forth.

PPE 13 may include a number of components for which the physical spatialrelationship between the components determines or otherwise indicatesthe operational status of the PPE for some types of PPE. For example, aface shield attached to a helmet or hardhat may be in an up or open(i.e., standby) position that provides no protection to the worker 10 orin a down or closed (i.e., active) position that provides protection tothe worker 10. As another example, earmuffs attached to a helmet orhardhat may be positioned in an up (i.e., standby) position such thatthe earmuffs are not positioned over the worker 10 ears and provide nohearing protection to the worker 10, or the earmuffs may be positionedin a down position (i.e., active) such that the earmuffs are positionedover the worker 10 ears and provide hearing protection to the worker 10.A pair of components of PPE, such as those described above, may bereferred to herein as an equipment pair, even if such components aretypically used together as a single article of PPE. The operationalstatus of a pair of PPE may be indicative of a safety condition.

A spatial relation between two or more PPE 13, for some types of PPE,may indicate the operational status of one or more of the PPE. Forinstance, a hardhat may be positioned on a worker's head in an activeposition according to a first orientation. Earmuffs may be positioned toenclose the worker's ears in an active position or positioned to notenclose the worker's ears in a standby position, according to a secondorientation (typically vertical for over-the-head earmuffs). Thedifference between the first orientation of the helmet in the activeposition and the second orientation of the earmuffs may indicate whetherthe earmuffs are in an active position. The operational status of a pairof PPE may be indicative of a safety condition.

A spatial relation between an article, machine, signage or other itemsof a work environment 8 and a PPE for a worker 10 may indicate theoperational status of the PPE. For example, a machine of environment 8A,when activated, may create various proximity hazards. The distancebetween a PPE positioned on the worker 10 and the machine indicateswhether the worker is within a threshold distance for the proximityhazard, and the distance is thus indicative of a safety condition.

Each of PPE 13 may in some examples include embedded sensors ormonitoring devices and processing electronics configured to capture datain real-time as a user (e.g., worker) engages in activities whilewearing the respirators. PPE 13 may include a number of sensors forsensing or controlling the operation of such components. A head top mayinclude, as examples, a head top visor position sensor, a head toptemperature sensor, a head top motion sensor, a head top impactdetection sensor, a head top position sensor, a head top battery levelsensor, a head-top head detection sensor, an ambient noise sensor, orthe like. A blower may include, as examples, a blower state sensor, ablower pressure sensor, a blower run time sensor, a blower temperaturesensor, a blower battery sensor, a blower motion sensor, a blower impactdetection sensor, a blower position sensor, or the like. A filter mayinclude, as examples, a filter presence sensor, a filter type sensor, orthe like. Each of the above-noted sensors may generate usage data, asdescribed herein.

In addition, each of PPE 13 may include one or more output devices foroutputting data that is indicative of operation of PPE 13 and/orgenerating and outputting communications to the respective worker 10.For example, PPE 13 may include one or more devices to generate audiblefeedback (e.g., one or more speakers), visual feedback (e.g., one ormore displays, light emitting diodes (LEDs) or the like), or tactilefeedback (e.g., a device that vibrates or provides other hapticfeedback).

In general, each of environments 8 include computing facilities (e.g., alocal area network) by which PPE 13 are able to communicate with PPEMS6. For examples, environments 8 may be configured with wirelesstechnology, such as 802.11 wireless networks, 802.15 ZigBee networks,and the like. In the example of FIG. 1, environment 8B includes a localnetwork 7 that provides a packet-based transport medium forcommunicating with PPEMS 6 via network 4. Environment 8B may includewireless access point 19 to provide support for wireless communications.In some examples, environment 8B may include a plurality of wirelessaccess points 19 that may be geographically distributed throughout theenvironment to provide support for wireless communications throughoutthe work environment.

Each of PPE 13 may be configured to communicate data, such as sensedmotions, events and conditions, via wireless communications, such as via802.11 WiFi protocols, Bluetooth protocol or the like. PPE 13 may, forexample, communicate directly with a wireless access point 19. Asanother example, each worker 10 may be equipped with a respective one ofwearable communication hubs 14A-14N that enable and facilitatecommunication between PPE 13 and PPEMS 6. For example, PPE 13 for therespective workers 10 may communicate with a respective communicationhub 14 via Bluetooth or other short-range protocol, and thecommunication hubs may communicate with PPEMS 6 via wirelesscommunications processed by wireless access point 19. Although shown aswearable devices, hubs 14 may be implemented as stand-alone devicesdeployed within environment 8B.

In general, each of hubs 14 operates as a wireless device for PPE 13relaying communications to and from PPE 13, and may be capable ofbuffering usage data in case communication is lost with PPEMS 6.Moreover, each of hubs 14 is programmable via PPEMS 6 so that localalert rules may be installed and executed without requiring a connectionto the cloud. As such, each of hubs 14 provides a relay of streams ofusage data from PPE 13 and/or other PPEs within the respectiveenvironment, and provides a local computing environment for localizedalerting based on streams of events in the event communication withPPEMS 6 is lost.

As shown in the example of FIG. 1, an environment, such as environment8B, may also contain one or more wireless-enabled beacons, such asbeacons 17A-17B, that provide accurate location information within thework environment. For example, beacons 17A-17B may be GPS-enabled suchthat a controller within the respective beacon may be able to preciselydetermine the position of the respective beacon. Based on wirelesscommunications with one or more of beacons 17, a given PPE 13 orcommunication hub 14 worn by a worker 10 is configured to determine thelocation of the worker within work environment 8B. In this way, eventdata reported to PPEMS 6 may be stamped with positional information toaid analysis, reporting and analytics performed by the PPEMS.

In addition, an environment, such as environment 8B, may also includeone or more wireless-enabled sensing stations, such as sensing stations21A, 21B. Each sensing station 21 includes one or more sensors and acontroller configured to output data indicative of sensed environmentalconditions. Moreover, sensing stations 21 may be positioned withinrespective geographic regions of environment 8B or otherwise interactwith beacons 17 to determine respective positions and include suchpositional information when reporting environmental data to PPEMS 6. Assuch, PPEMS 6 may be configured to correlate the sensed environmentalconditions with the particular regions and, therefore, may utilize thecaptured environmental data when processing event data received from PPE13. For example, PPEMS 6 may utilize the environmental data to aidgenerating alerts or other instructions for PPE 13 and for performingpredictive analytics, such as determining any correlations betweencertain environmental conditions (e.g., heat, humidity, visibility) withabnormal worker behavior or increased safety events. As such, PPEMS 6may utilize current environmental conditions to aid prediction andavoidance of imminent safety events. Example environmental conditionsthat may be sensed by sensing stations 21 include but are not limited totemperature, humidity, presence of gas, pressure, visibility, wind andthe like.

In example implementations, an environment, such as environment 8B, mayalso include one or more safety stations 15 distributed throughout theenvironment to provide viewing stations for accessing PPE 13. Safetystations 15 may allow one of workers 10 to check out PPE 13 and/or othersafety equipment, verify that safety equipment is appropriate for aparticular one of environments 8, and/or exchange data. For example,safety stations 15 may transmit alert rules, software updates, orfirmware updates to PPE 13 or other equipment. Safety stations 15 mayalso receive data cached on PPE 13, hubs 14, and/or other safetyequipment. That is, while PPE 13 (and/or data hubs 14) may typicallytransmit usage data from sensors of PPE 13 via network 4 in real time ornear real time, PPE 13 (and/or data hubs 14) may not have connectivityto network 4 in some instances, situations, or conditions. In suchcases, PPE 13 (and/or data hubs 14) may store usage data locally andtransmit the usage data to safety stations 15 upon being in proximitywith safety stations 15. Safety stations 15 may then obtain the datafrom sensors of PPE 13 and connect to network 4 to transmit the usagedata.

In addition, each of environments 8 may include computing facilitiesthat provide an operating environment for end-user computing devices 16for interacting with PPEMS 6 via network 4. For example, each ofenvironments 8 typically includes one or more safety managersresponsible for overseeing safety compliance within the environment. Ingeneral, each user 20 interacts with computing devices 16 to accessPPEMS 6. Each of environments 8 may include systems. Similarly, remoteusers may use computing devices 18 to interact with PPEMS via network 4.For purposes of example, the end-user computing devices 16 may belaptops, desktop computers, mobile devices such as tablets or so-calledsmart phones and the like.

Users 20, 24 interact with PPEMS 6 to control and actively manage manyaspects of safely equipment utilized by workers 10, such as accessingand viewing usage records, analytics and reporting. For example, users20, 24 may review usage information acquired and stored by PPEMS 6,where the usage information may include data specifying starting andending times over a time duration (e.g., a day, a week, etc.), datacollected during particular events, such as lifts of a PPE 13 visor,removal of PPE 13 from a worker 10, changes to operating parameters ofPPE 13, status changes to components of PPE 13 (e.g., a low batteryevent), motion of workers 10, detected impacts to PPE 13 or hubs 14,sensed data acquired from the user, environment data, and the like. Inaddition, users 20, 24 may interact with PPEMS 6 to perform assettracking and to schedule maintenance events for individual pieces ofsafety equipment, e.g., PPE 13, to ensure compliance with any proceduresor regulations. PPEMS 6 may allow users 20, 24 to create and completedigital checklists with respect to the maintenance procedures and tosynchronize any results of the procedures from computing devices 16, 18to PPEMS 6.

Further, PPEMS 6 may integrate an event processing platform configuredto process thousand or even millions of concurrent streams of eventsfrom digitally enabled PPEs, such as PPE 13. An underlying analyticsengine of PPEMS 6 may apply historical data and models to the inboundstreams to compute assertions, such as identified anomalies or predictedoccurrences of safety events based on conditions or behavior patterns ofworkers 10. Further, PPEMS 6 may provide real-time alerting andreporting to notify workers 10 and/or users 20, 24 of any predictedevents, anomalies, trends, and the like.

The analytics engine of PPEMS 6 may, in some examples, apply analyticsto identify relationships or correlations between sensed worker data,environmental conditions, geographic regions and other factors andanalyze the impact on safety events. PPEMS 6 may determine, based on thedata acquired across populations of workers 10, which particularactivities, possibly within certain geographic region, lead to, or arepredicted to lead to, unusually high occurrences of safety events.

In this way, PPEMS 6 tightly integrates comprehensive tools for managingpersonal protective equipment with an underlying analytics engine andcommunication system to provide data acquisition, monitoring, activitylogging, reporting, behavior analytics and alert generation. Moreover,PPEMS 6 provides a communication system for operation and utilization byand between the various elements of system 2. Users 20, 24 may accessPPEMS to view results on any analytics performed by PPEMS 6 on dataacquired from workers 10. In some examples, PPEMS 6 may present aweb-based interface via a web server (e.g., an HTTP server) orclient-side applications may be deployed for devices of computingdevices 16, 18 used by users 20, 24, such as desktop computers, laptopcomputers, mobile devices such as smartphones and tablets, or the like.

In some examples, PPEMS 6 may provide a database query engine fordirectly querying PPEMS 6 to view acquired safety information,compliance information and any results of the analytic engine, e.g., bythe way of dashboards, alert notifications, reports and the like. Thatis, users 20, 24 or software executing on computing devices 16, 18, maysubmit queries to PPEMS 6 and receive data corresponding to the queriesfor presentation in the form of one or more reports or dashboards. Suchdashboards may provide various insights regarding system 2, such asbaseline (“normal”) operation across worker populations, identificationsof any anomalous workers engaging in abnormal activities that maypotentially expose the worker to risks, identifications of anygeographic regions within environments 8 for which unusually anomalous(e.g., high) safety events have been or are predicted to occur,identifications of any of environments 8 exhibiting anomalousoccurrences of safety events relative to other environments, and thelike.

As illustrated in detail below, PPEMS 6 may simplify workflows forindividuals charged with monitoring and ensure safety compliance for anentity or environment. That is, PPEMS 6 may enable active safetymanagement and allow an organization to take preventative or correctionactions with respect to certain regions within environments 8,particular pieces of safety equipment or individual workers 10, defineand may further allow the entity to implement workflow procedures thatare data-driven by an underlying analytical engine.

As one example, the underlying analytical engine of PPEMS 6 may beconfigured to compute and present customer-defined metrics for workerpopulations within a given environment 8 or across multiple environmentsfor an organization as a whole. For example, PPEMS 6 may be configuredto acquire data and provide aggregated performance metrics and predictedbehavior analytics across a worker population (e.g., across workers 10of either or both of environments 8A, 8B). Furthermore, users 20, 24 mayset benchmarks for occurrence of any safety incidences, and PPEMS 6 maytrack actual performance metrics relative to the benchmarks forindividuals or defined worker populations.

As another example, PPEMS 6 may further trigger an alert if certaincombinations of conditions are present, e.g., to accelerate examinationor service of a safety equipment, such as one of PPE 13. In this manner,PPEMS 6 may identify individual PPE 13 or workers 10 for which themetrics do not meet the benchmarks and prompt the users to interveneand/or perform procedures to improve the metrics relative to thebenchmarks, thereby ensuring compliance and actively managing safety forworkers 10.

Item 26 located in environment 8B may be a machine, wall, signage,safety device, station, or other item. Item 26 may be stationary, atleast during worker operation within the environment 8B.

In accordance with techniques described herein, PPE 13 are embodied withat least one optical pattern visible on a surface of the PPE 13. In theexample of FIG. 1, PPE 13A worn by worker 10A has embodied therein anoptical pattern 22A and an optical pattern 23A. Optical pattern 22A andthe optical pattern 23A are associated with one another (“paired”) inPPEMS 6. PPE 13N worn by worker 10N has embodied thereon an opticalpattern 22N. An item 26 located in environment 8B has embodied thereinan optical pattern 23N. Optical pattern 22N and the optical pattern 23Nare associated with one another in PPEMS 6.

Each of optical patterns 22, 23 may be a machine-readable code. Themachine-readable code may be printed with infrared absorbing ink toenable an infrared camera to obtain images that can be readily processedto identify the machine-readable code. The machine-readable code may bea unique identifier within the scope of PPE managed by PPEMS 6. In somecases, pairs of optical patterns 22, 23 may have the same opticalpattern and the machine-readable code to indicate that optical patternsshould be paired by PPEMS 6. PPEMS 6 may use the machine-readable codeto uniquely identify the corresponding PPE 13, component thereof, oritem 26 on which the optical pattern is embodied. An optical pattern canbe embodied on different types of PPE 13, such as protective eyewear,helmets, face shields, ear muffs, fall protection harness, coveralls, orrespirators.

Optical patterns 22, 23 are embodied on a surface of a PPE 13 to bevisible such that image capture device 28 may obtain images of theoptical patterns 22, 23 when workers 10 are working in the environments8. In some examples, each of optical patterns 22, 23 may be embodied ona label or tag affixed to the corresponding PPE 13 or item 26 using anadhesive, clip, or other fastening means to be substantially immobilewith respect to the PPE 13, item 26, or components thereof to which theoptical pattern is affixed while workers 10 are working in environments8. In such examples, optical patterns 22, 23 may be referred to as“optical tags” or “optical labels.” Some examples of optical tags areapproximately 4 cm×4 cm in dimension. Optical tags may be affixed to avariety of types of PPEs 13.

An optical tag having an optical pattern embodied thereon may be aretroreflective tag with a machine-readable code. The machine-readablecode may be printed with infrared absorbing ink to enable an infraredcamera to obtain images that can be readily processed to identify themachine-readable code. The optical tag may include an adhesive layer anda retroreflective sheeting layer printed with the machine-readable code.In some instances, the optical tag includes an additional mirror filmlayer that is laminated over the machine-readable code. The mirror filmis infrared transparent such that the machine-readable code is notvisible in ambient light but readily detectable within images obtainedby an infrared camera (e.g., with some instances of image capture device28). The machine-readable code may be a unique identifier within thescope of PPE managed by PPEMS 6. PPEMS 6 may use the machine-readablecode to uniquely identify the optical tag 22, 23 and the correspondingPPE 13, component thereof, or item 26 to which the optical tag 22, 23 isaffixed. An optical tag can be adhered to different types of PPE 13,such as protective eyewear, helmets, face shields, ear muffs, fallprotection harness, coveralls, or respirators. Additional description ofa mirror film is found in PCT Appl. No. PCT/US2017/014031, filed Jan.19, 2017, which is incorporated by reference herein in its entirety.

In some examples, a PPE 13, component thereof, or item 26 ismanufactured with an optical pattern 22, 23 embodied thereon. In someexamples, an optical pattern 22, 23 may be printed, stamped, engraved,or otherwise embodied directly on a surface of the PPE 13, componentthereof, or item 26. In some examples, a mix of types of embodiments ofthe optical patterns may be present in the environments. For example,optical pattern 23N may be printed on item 26, while optical pattern 22Nis printed on a tag affixed to PPE 13N. Optical patterns 22A, 23A mayboth be printed on tags affixed to components of PPE 13A.

Each of optical patterns 22, 23 has a relative orientation with respectto its corresponding PPE 13, component of PPE 13, or item 26. In theillustrated example, optical pattern 22A has a relative orientation withrespect to a helmet/hardhat of PPE 13A, optical pattern 23A has arelative orientation with respect to a visor of PPE 13A, optical pattern22N has a relative orientation with respect to a helmet/hardhat of PPE13N, and optical pattern 23N has a relative orientation with respect toitem 26. Each pair of optical patterns 22, 23 has a relative orientationto one another and, by extension, this relative orientation isindicative of the relative orientation of the pair of PPE 13,components, or items to which the respective patterns from the pair ofoptical patterns 22, 23 are affixed. Each of optical patterns 22, 23 mayvisually indicate an orientation of the optical pattern. For example, anoptical pattern may be such that a top or other side of the opticalpattern may be readily visually identifiable regardless of theorientation in which the optical pattern is positioned. In this way,PPEMS 6 may determine from an image of an optical pattern an orientationof the optical pattern with respect to a coordinate system, e.g., alocal coordinate system defined at least in part by an orientation ofimage capture device 28, or a global coordinate system. Further, PPEMS 6may determine from an image of a first optical pattern and a secondoptical pattern a difference in between the orientations of the firstoptical pattern and the second optical pattern, which is the relativeorientation between the first optical pattern and the second opticalpattern.

In the illustrated example, for instance, the relative orientation ofoptical patterns 22A, 23A indicates the relative orientation of thehelmet/hardhat of PPE 13A (to which optical pattern 22A is affixed) andthe visor of PPE 13A (to which optical pattern 23A is affixed). Therelative orientation of optical patterns 22N, 23N indicates the relativeorientation of PPE 13N and item 26.

If an orientation of any of PPE 13, components thereof, or item 26changes, the relative orientation of the corresponding pair of opticalpatterns 22, 23 changes. For example, a visor for PPE 13A raised instandby position results in a relative orientation for the pair ofoptical patterns 22A, 23A that is different than when the visor for PPE13A is down in active position. Accordingly, the relative orientation ofoptical patterns 22A, 23A indicates whether the visor is in active orstandby position.

Each pair of optical patterns 22, 23 also has a positional relation toone another. For example, each optical pattern for pair of opticalpatterns 22, 23 is positioned at any given time at a location in anenvironment 8. The positional relation defines a distance between thepair of optical patterns 22, 23. If a position of any of PPE 13,components thereof, or item 26 changes, the position relation of thecorresponding pair of optical patterns 22, 23 changes. For example, ifworker 10N wearing PPE 13N moves, the positional relation between pairof optical patterns 22N, 23N changes. The pair of optical patterns 22N,23N may become closer or farther apart, for instance.

The relative orientation and positional relation between a pair ofoptical patterns 22, 23 are aspects of an overall spatial relationbetween the pair of optical patterns 22, 23. As explained above, thespatial relation between the pair of optical patterns 22, 23 indicatesthe spatial relation between the corresponding PPE 13, componentsthereof, or item on which the pair of optical patterns 22, 23 areembodied.

Image capture device 28 obtains and stores, at least temporarily, images27A-27N of environment 8B. PPEMS 6 obtains images 27 from image capturedevice 28, e.g., via network 4, in near real-time for near real-timeprocessing. Image capture device 28 may obtain multiple images 27A at afrequency at a position and orientation of image capture device 28. Forinstance, image capture device 28 may obtain an instance of image 27Aonce every second.

Image capture device 28 may be an optical camera, video camera, infraredor other non-human-visible spectrum camera, or a combination thereof.Image capture device 28 may be stationary or mobile with respect toenvironment 8B. For example, image capture device 28 may be a head-topcamera worn by a worker or supervisor. An orientation of image capturedevice 28 may be fixed or moveable along one or more degrees of freedom.Image capture device 28 includes a wired or wireless communication linkwith PPEMS 6. For instance, image capture device 28 may transmit images27 to PPEMS 6 or to a storage system (not shown in FIG. 1) via network6. Alternatively, PPEMS 6 may read images 27 from a storage device forimage capture device 28, or from the storage system (again, not shown inFIG. 1). Although only a single image capture device 28 is depicted,environment 8B may include multiple image capture devices 28 positionedabout the environment 8B and oriented in different orientation in orderto capture images of environment 8B from different positions andorientations, which results images that provide a more comprehensiveview of the environment. As described herein, images generated by animage capture device 28 may refer to images generated by multiple imagecapture devices 28. The multiple image capture devices 28 may have knownspatial inter-relations among them to permit determination of spatialrelations between optical tags in respective images generated byrespective image capture devices 28.

Images 27 may be optical images or infrared or other non-human-visiblespectrum images. Images 27 include images of optical patterns 22, 23.

PPEMS 6 processes images 27 to identify optical patterns 22, 23. PPEMS 6may process images 27 to identify the machine-readable codes of theoptical patterns 22, 23. PPEMS 6 may process images 27 to determine aspatial relation between pairs of optical patterns 22, 23. To determinethe spatial relation between pairs of optical patterns 22, 23, PPEMS 6may determine, from one or more of the images, a position of eachoptical pattern and/or an orientation of each optical pattern withrespect to a coordinate system. PPEMS 6 may also or alternativedetermine, from an image, a relative position of the pair of opticalpatterns 22, 23 and/or a relative orientation of the pair of opticalpatterns 22, 23.

For example, PPEMS 6 may process image 27A to determine the spatialrelation between optical patterns 22A, 23A to identify a correspondingsafety condition. The spatial relation, more particularly the relativeorientation, may indicate that a visor of PPE 13A is in a closed, activeposition (as illustrated). Alternatively, the spatial relation mayindicate that the visor is in an open, standby position such thereexists a safety condition and, more specifically, a visor event.

As another example, PPEMS 6 may process image 27N to determine thespatial relation between optical patterns 22N, 23N to identify acorresponding safety condition. The spatial relation may indicate thatPPE 13N (and by extension worker 10N) is a distance from item 26, e.g.,3 meters. The spatial relation may indicate the PPE 13N has a relativeorientation to item 26, e.g., 90 degrees. The relative orientationbetween optical patterns 22N, 23N may indicate that worker 10N is proneand has experienced a fall, a trauma, and/or has swooned such that theworker 10N has had a worker-down event. The relative orientation mayalternatively indicate that a helmet/hardhat PPE 13N is not positionedon the head of worker 10N, which may be a safety condition.

As another example, PPEMS 6 may process an image 27 to determine aspatial relation between a pair of optical patterns 22, 23 embodied oncomponents of a hearing protection apparatus-type PPE 13 to identify acorresponding safety condition. The relative orientation of the pair ofoptical patterns may indicate that the ear muffs are positioned in astandby position, i.e., not positioned over the ears of a worker inenvironment 8 and thus incapable of attenuating sound for the workerwearing the PPE 13, indicative of a safety condition and, morespecifically, a hearing protection event.

As another example, PPEMS 6 may process an image 27 to determine aspatial relation between a pair of optical patterns 22, 23 embodied oncomponents of a respirator or other breathing protection apparatus-typePPE 13 to identify a corresponding safety condition. The relativeorientation of the pair of optical patterns may indicate that therespirator is positioned in a standby position, i.e., not positionedover the nose of a worker in environment 8 and thus incapable ofproviding safe breathable air for the worker wearing the PPE 13,indicative of a safety condition and, more specifically, a respiratorprotection event.

Other examples involving other types of PPE 13 are contemplated.

In some examples, PPEMS 6 may use a spatial relation between one pair ofoptical patterns 22, 23 for a PPE 13 and a spatial relation betweenanother pair of optical patterns 22, 23 to determine whether a safetycondition exists for a worker. For example, PPEMS 6 may process images27A, 27N (or a single image 27 having images of optical patterns 22A,23A, and 23N) to determine a spatial relation between optical pattern22A and 23N. The spatial relation may indicate that worker 10A wearingPPE 13A is positioned within a threshold distance for a proximity hazardassociated with item 26. For instance, item 26 may be a welding stationand workers within the threshold distance may experience eye damage ifnot protected by appropriate PPE. If PPE 13A is a welding mask, PPEMS 6may process images of optical patterns 22A, 23A to determine (1) from amachine-readable code of one of optical patterns 22A, 23A that PPE 13Ais a welding mask, and (2) a spatial relation between optical patterns22A, 23A. If the spatial relation indicates the welding mask is in anopen, standby position, this may indicate a safety condition and PPEMS 6may output a visor event or perform another operation in response to thesafety condition.

Other spatial relation combinations of optical patterns 22, 23 arecontemplated, such as proximity hazards associated with force-inducedtrauma, lacerations, heat, noxious gases, falls, noise, and so forth,and the corresponding types of PPEs 13 intended to mitigate the dangersfrom such hazards.

In response to identifying the presence or absence of a safetycondition, PPEMS 6 may output an event to notify a worker 10 orsupervisor, shutdown a machine, or perform another operation. Byidentifying safety conditions using optical patterns in captured images27 of PPEs 13, the techniques may be more versatile and widelyapplicable than using devices tied to the PPEs 13, such as sensors,locks, barriers, or other devices for indicating or ensuring anoperational status of the PPE 13 (e.g., open vs. closed) or forindicating an unsafe spatial relationship between a PPE 13 and anotherapparatus. As another example, workers 10 may be less able to defeat thesafety techniques described herein. As a still further example, thePPEMS 6 applying techniques described herein may be able to determine asafety condition for a PPE 13 without requiring a communication sessionor channel with the PPE 13, unlike other systems that may rely onreceiving a communication signal from a PPE 13 indicating an operationalstatus of the PPE 13. This may reduce a cost and/or improve areliability of system 2 over other systems that rely on explicitcommunication. Furthermore, in some instances, the PPEMS 6 may be ableto process a captured image that includes images of multiple PPEs 13 andrespective optical patterns, which allows the PPEMS 6 to concurrentlyprocess and identify potential safety for the multiple PPEs 13 withouthaving to process communication signals from each of the PPEs 13.

FIG. 2 is a block diagram providing an operating perspective of PPEMS 6when hosted as cloud-based platform capable of supporting multiple,distinct work environments 8 having an overall population of workers 10that have a variety of communication enabled personal protectiveequipment (PPE) 13, in accordance with techniques described herein. Inthe example of FIG. 2, the components of PPEMS 6 are arranged accordingto multiple logical layers that implement the techniques of thedisclosure. Each layer may be implemented by one or more modulescomprised of hardware, software, or a combination of hardware andsoftware.

In FIG. 2, personal protective equipment (PPEs) 13 and/or otherequipment, either directly or by way of HUBs 14, safety stations 15, aswell as computing devices 60, operate as clients 63 that communicatewith PPEMS 6 via interface layer 64. Computing devices 60 typicallyexecute client software applications, such as desktop applications,mobile applications, and web applications. Computing devices 60 mayrepresent any of computing devices 16, 18 of FIG. 1. Examples ofcomputing devices 60 may include, but are not limited to a portable ormobile computing device (e.g., smartphone, wearable computing device,tablet), laptop computers, desktop computers, smart televisionplatforms, and servers, to name only a few examples.

Some types or instances of PPEs 13 may communicate with PPEMS 6(directly or via hubs 14) to provide streams of data acquired fromembedded sensors and other monitoring circuitry and receive from PPEMS 6alerts, configuration and other communications. However, a PPE 13 neednot be able to communicate with PPEMS 6 to have one or more opticalpatterns embodied thereon and usable by PPEMS 6 to identify a safetycondition associated with the PPE.

Client applications executing on computing devices 60 may communicatewith PPEMS 6 to send and receive information that is retrieved, stored,generated, and/or otherwise processed by services 68. For instance, theclient applications may request and edit safety event informationincluding analytical data stored at and/or managed by PPEMS 6. In someexamples, client applications may request and display aggregate safetyevent information that summarizes or otherwise aggregates numerousindividual instances of safety events and corresponding data obtainedfrom PPEs 13 and/or generated by PPEMS 6. The client applications mayinteract with PPEMS 6 to query for analytics information about past andpredicted safety events, behavior trends of workers 10, to name only afew examples. In some examples, the client applications may output fordisplay information received from PPEMS 6 to visualize such informationfor users of clients 63. As further illustrated and described in below,PPEMS 6 may provide information to the client applications, which theclient applications output for display in user interfaces. Additionalinformation is found in U.S. application Ser. No. 15/109,564, filed Jun.23, 2016, entitled “Indicating Hazardous Exposure in a Supplied AirRespirator System,” which is incorporated herein by reference in itsentirety.

Clients applications executing on computing devices 60 may beimplemented for different platforms but include similar or the samefunctionality. For instance, a client application may be a desktopapplication compiled to run on a desktop operating system, such asMicrosoft Windows, Apple OS X, or Linux, to name only a few examples. Asanother example, a client application may be a mobile applicationcompiled to run on a mobile operating system, such as Google Android,Apple iOS, Microsoft Windows Mobile, or BlackBerry OS to name only a fewexamples. As another example, a client application may be a webapplication such as a web browser that displays web pages received fromPPEMS 6. In the example of a web application, PPEMS 6 may receiverequests from the web application (e.g., the web browser), process therequests, and send one or more responses back to the web application. Inthis way, the collection of web pages, the client-side processing webapplication, and the server-side processing performed by PPEMS 6collectively provides the functionality to perform techniques of thisdisclosure. In this way, client applications use various services ofPPEMS 6 in accordance with techniques of this disclosure, and theapplications may operate within various different computing environment(e.g., embedded circuitry or processor of a PPE, a desktop operatingsystem, mobile operating system, or web browser, to name only a fewexamples).

As shown in FIG. 2, PPEMS 6 includes an interface layer 64 thatrepresents a set of application programming interfaces (API) or protocolinterface presented and supported by PPEMS 6. Interface layer 64initially receives messages from any of clients 63 for furtherprocessing at PPEMS 6. Interface layer 64 may therefore provide one ormore interfaces that are available to client applications executing onclients 63. In some examples, the interfaces may be applicationprogramming interfaces (APIs) that are accessible over a network.Interface layer 64 may be implemented with one or more web servers. Theone or more web servers may receive incoming requests, process and/orforward information from the requests to services 68, and provide one ormore responses, based on information received from services 68, to theclient application that initially sent the request. In some examples,the one or more web servers that implement interface layer 64 mayinclude a runtime environment to deploy program logic that provides theone or more interfaces. As further described below, each service mayprovide a group of one or more interfaces that are accessible viainterface layer 64.

In some examples, interface layer 64 may provide Representational StateTransfer (RESTful) interfaces that use HTTP methods to interact withservices and manipulate resources of PPEMS 6. In such examples, services68 may generate JavaScript Object Notation (JSON) messages thatinterface layer 64 sends back to the client application 61 thatsubmitted the initial request. In some examples, interface layer 64provides web services using Simple Object Access Protocol (SOAP) toprocess requests from client applications 61. In still other examples,interface layer 64 may use Remote Procedure Calls (RPC) to processrequests from clients 63. Upon receiving a request from a clientapplication to use one or more services 68, interface layer 64 sends theinformation to application layer 66, which includes services 68.

As shown in FIG. 2, PPEMS 6 also includes an application layer 66 thatrepresents a collection of services for implementing much of theunderlying operations of PPEMS 6. Application layer 66 receivesinformation included in requests received from client applications 61and further processes the information according to one or more ofservices 68 invoked by the requests. Application layer 66 may beimplemented as one or more discrete software services executing on oneor more application servers, e.g., physical or virtual machines. Thatis, the application servers provide runtime environments for executionof services 68. In some examples, the functionality interface layer 64as described above and the functionality of application layer 66 may beimplemented at the same server.

Application layer 66 may include one or more separate software services68, e.g., processes that communicate, e.g., via a logical service bus 70as one example. Service bus 70 generally represents logicalinterconnections or set of interfaces that allows different services tosend messages to other services, such as by a publish/subscriptioncommunication model. For instance, each of services 68 may subscribe tospecific types of messages based on criteria set for the respectiveservice. When a service publishes a message of a particular type onservice bus 70, other services that subscribe to messages of that typewill receive the message. In this way, each of services 68 maycommunicate information to one another. As another example, services 68may communicate in point-to-point fashion using sockets or othercommunication mechanisms. Before describing the functionality of each ofservices 68, the layers are briefly described herein.

Data layer 72 of PPEMS 6 represents a data repository that providespersistence for information in PPEMS 6 using one or more datarepositories 74. A data repository, generally, may be any data structureor software that stores and/or manages data. Examples of datarepositories include but are not limited to relational databases,multi-dimensional databases, maps, and hash tables, to name only a fewexamples. Data layer 72 may be implemented using Relational DatabaseManagement System (RDBMS) software to manage information in datarepositories 74. The RDBMS software may manage one or more datarepositories 74, which may be accessed using Structured Query Language(SQL). Information in the one or more databases may be stored,retrieved, and modified using the RDBMS software. In some examples, datalayer 72 may be implemented using an Object Database Management System(ODBMS), Online Analytical Processing (OLAP) database or other suitabledata management system.

As shown in FIG. 2, each of services 68A-68J (“services 68”) isimplemented in a modular form within PPEMS 6. Although shown as separatemodules for each service, in some examples the functionality of two ormore services may be combined into a single module or component. Each ofservices 68 may be implemented in software, hardware, or a combinationof hardware and software. Moreover, services 68 may be implemented asstandalone devices, separate virtual machines or containers, processes,threads or software instructions generally for execution on one or morephysical processors.

In some examples, one or more of services 68 may each provide one ormore interfaces that are exposed through interface layer 64.Accordingly, client applications of computing devices 60 may call one ormore interfaces of one or more of services 68 to perform techniques ofthis disclosure.

In accordance with techniques of the disclosure, services 68 may includean event processing platform including a pattern processor service 68Jand an event endpoint frontend 68A, event selector 68B, event processor68C and high priority (HP) event processor 68D.

Pattern processor service 68J obtains images 27 generated by imagecapture device 28 and processes images 27 to identify safety conditionsand, in some cases, to generate events based on the safety conditions.Pattern service 68J may add generated events to event streams 29 forprocessing by other services, as described below.

Event endpoint frontend 68A operates as a frontend interface forexchanging communications with hubs 14 and in some cases with one ormore of PPEs 13. In other words, event endpoint frontend 68A operates toas a frontline interface to safety equipment deployed withinenvironments 8 and utilized by workers 10. In some instances, eventendpoint frontend 68A may be implemented as a plurality of tasks or jobsspawned to receive individual inbound communications of event streams 69from the PPEs 13 carrying data sensed and captured by the safetyequipment. When receiving event streams 69, for example, event endpointfrontend 68A may spawn tasks to quickly enqueue an inboundcommunication, referred to as an event, and close the communicationsession, thereby providing high-speed processing and scalability. Eachincoming communication may, for example, carry data recently captureddata representing sensed conditions, motions, temperatures, actions orother data, generally referred to as events. Communications exchangedbetween the event endpoint frontend 68A and the PPEs 13/hubs 14 may bereal-time or pseudo real-time depending on communication delays andcontinuity.

Event selector 68B operates on the stream of events 69 received fromPPEs 13 and/or hubs 14 via frontend 68A and determines, based on rulesor classifications, priorities associated with the incoming events.Based on the priorities, event selector 68B enqueues the events forsubsequent processing by event processor 68C or high priority (HP) eventprocessor 68D. Additional computational resources and objects may bededicated to HP event processor 68D so as to ensure responsiveness tocritical events, such as incorrect usage of PPEs, use of incorrectfilters and/or respirators based on geographic locations and conditions,failure to properly secure SRLs 11 and the like. Responsive toprocessing high priority events, HP event processor 68D may immediatelyinvoke notification service 68E to generate alerts, instructions,warnings or other similar messages to be output to PPEs 13, hubs 14, ordevices used by users 20, 24. Events not classified as high priority areconsumed and processed by event processor 68C.

In general, event processor 68C or high priority (HP) event processor68D operate on the incoming streams of events to update event data 74Awithin data repositories 74. In general, event data 74A may include allor a subset of usage data generated by pattern service 68J or by PPEs13. For example, in some instances, event data 74A may include entirestreams of samples of data obtained from electronic sensors of PPEs 13.In other instances, event data 74A may include a subset of such data,e.g., associated with a particular time period or activity of PPEs 13.Event data 74 generated by pattern service 68J may include a descriptionof a safety condition identified by pattern service. Alternatively, suchevent data may include a stream of data describing spatial relationsbetween pairs of optical patterns over time for further processing byevent processors 68C, 68D, as well as stream analytics service 68F insome cases.

Event processors 68C, 68D may create, read, update, and delete eventinformation stored in event data 74A. Event information for may bestored in a respective database record as a structure that includesname/value pairs of information, such as data tables specified inrow/column format. For instance, a name (e.g., column) may be “workerID” and a value may be an employee identification number. An eventrecord may include information such as, but not limited to: workeridentification, PPE identification, acquisition timestamp(s) and dataindicative of one or more sensed parameters.

In addition, event selector 68B directs the incoming stream of events tostream analytics service 68F, which is configured to perform in depthprocessing of the incoming stream of events to perform real-timeanalytics. Stream analytics service 68F may, for example, be configuredto process and compare multiple streams of event data 74A withhistorical data and models 74B in real-time as event data 74A isreceived. In this way, stream analytic service 68D may be configured todetect anomalies, transform incoming event data values, trigger alertsupon detecting safety concerns based on conditions or worker behaviors.Historical data and models 74B may include, for example, specifiedsafety rules, business rules and the like. In addition, stream analyticservice 68D may generate output for communicating to PPEs 13 bynotification service 68F or computing devices 60 by way of recordmanagement and reporting service 68D.

In this way, analytics service 68F may process inbound streams ofevents, potentially hundreds or thousands of streams of events to applyhistorical data and models 74B to compute assertions, such as identifiedanomalies or predicted occurrences of imminent safety events based onconditions or behavior patterns of the workers. Analytics service 68Fpublish the assertions to notification service 68F and/or recordmanagement by service bus 70 for output to any of clients 63.

In this way, analytics service 68F may be configured as an active safetymanagement system that predicts imminent safety concerns and providesreal-time alerting and reporting. In addition, analytics service 68F maybe a decision support system that provides techniques for processinginbound streams of event data to generate assertions in the form ofstatistics, conclusions, and/or recommendations on an aggregate orindividualized worker and/or PPE basis for enterprises, safety officersand other remote users. For instance, analytics service 68F may applyhistorical data and models 74B to determine, for a particular worker,the likelihood that a safety event is imminent for the worker based ondetected behavior or activity patterns, environmental conditions andgeographic locations. In some examples, analytics service 68F maydetermine whether a worker is currently impaired, e.g., due toexhaustion, sickness or alcohol/drug use, and may require interventionto prevent safety events. As yet another example, analytics service 68Fmay provide comparative ratings of workers or type of safety equipmentin a particular environment 8.

Hence, analytics service 68F may maintain or otherwise use one or moremodels that provide risk metrics to predict safety events. Analyticsservice 68F may also generate order sets, recommendations, and qualitymeasures. In some examples, analytics service 68F may generate userinterfaces based on processing information stored by PPEMS 6 to provideactionable information to any of clients 63. For example, analyticsservice 68F may generate dashboards, alert notifications, reports andthe like for output at any of clients 63. Such information may providevarious insights regarding baseline (“normal”) operation across workerpopulations, identifications of any anomalous workers engaging inabnormal activities that may potentially expose the worker to risks,identifications of any geographic regions within environments for whichunusually anomalous (e.g., high) safety events have been or arepredicted to occur, identifications of any of environments exhibitinganomalous occurrences of safety events relative to other environments,and the like.

Although other technologies can be used, in one example implementation,analytics service 68F utilizes machine learning when operating onstreams of safety events so as to perform real-time analytics. That is,analytics service 68F includes executable code generated by applicationof machine learning to training data of event streams and known safetyevents to detect patterns. The executable code may take the form ofsoftware instructions or rule sets and is generally referred to as amodel that can subsequently be applied to event streams 69 for detectingsimilar patterns and predicting upcoming events.

Analytics service 68F may, in some example, generate separate models fora particular worker, a particular population of workers, a particularenvironment, or combinations thereof. Analytics service 68F may updatethe models based on usage data received from PPEs 13. For example,analytics service 68F may update the models for a particular worker, aparticular population of workers, a particular environment, orcombinations thereof based on data received from PPEs 13.

Alternatively, or in addition, analytics service 68F may communicate allor portions of the generated code and/or the machine learning models tohubs 16 (or PPEs 13) for execution thereon so as to provide localalerting in near-real time to PPEs. Example machine learning techniquesthat may be employed to generate models 74B can include various learningstyles, such as supervised learning, unsupervised learning, andsemi-supervised learning. Example types of algorithms include Bayesianalgorithms, Clustering algorithms, decision-tree algorithms,regularization algorithms, regression algorithms, instance-basedalgorithms, artificial neural network algorithms, deep learningalgorithms, dimensionality reduction algorithms and the like. Variousexamples of specific algorithms include Bayesian Linear Regression,Boosted Decision Tree Regression, and Neural Network Regression, BackPropagation Neural Networks, the Apriori algorithm, K-Means Clustering,k-Nearest Neighbor (kNN), Learning Vector Quantization (LUQ),Self-Organizing Map (SOM), Locally Weighted Learning (LWL), RidgeRegression, Least Absolute Shrinkage and Selection Operator (LASSO),Elastic Net, and Least-Angle Regression (LARS), Principal ComponentAnalysis (PCA) and Principal Component Regression (PCR).

Record management and reporting service 68G processes and responds tomessages and queries received from computing devices 60 via interfacelayer 64. For example, record management and reporting service 68G mayreceive requests from client computing devices for event data related toindividual workers, populations or sample sets of workers, geographicregions of environments 8 or environments 8 as a whole, or individual orgroups/types of PPEs 13. In response, record management and reportingservice 68G accesses event information based on the request. Uponretrieving the event data, record management and reporting service 68Gconstructs an output response to the client application that initiallyrequested the information. In some examples, the data may be included ina document, such as an HTML document, or the data may be encoded in aJSON format or presented by a dashboard application executing on therequesting client computing device. For instance, as further describedin this disclosure, example user interfaces that include the eventinformation are depicted in the figures.

As additional examples, record management and reporting service 68G mayreceive requests to find, analyze, and correlate PPE event information.For instance, record management and reporting service 68G may receive aquery request from a client application for event data 74A over ahistorical time frame, such as a user can view PPE event informationover a period of time and/or a computing device can analyze the PPEevent information over the period of time.

In example implementations, services 68 may also include securityservice 68H that authenticate and authorize users and requests withPPEMS 6. Specifically, security service 68H may receive authenticationrequests from client applications and/or other services 68 to accessdata in data layer 72 and/or perform processing in application layer 66.An authentication request may include credentials, such as a usernameand password. Security service 68H may query security data 74A todetermine whether the username and password combination is valid.Configuration data 74D may include security data in the form ofauthorization credentials, policies, and any other information forcontrolling access to PPEMS 6. As described above, security data 74A mayinclude authorization credentials, such as combinations of validusernames and passwords for authorized users of PPEMS 6. Othercredentials may include device identifiers or device profiles that areallowed to access PPEMS 6.

Security service 68H may provide audit and logging functionality foroperations performed at PPEMS 6. For instance, security service 68H maylog operations performed by services 68 and/or data accessed by services68 in data layer 72. Security service 68H may store audit informationsuch as logged operations, accessed data, and rule processing results inaudit data 74C. In some examples, security service 68H may generateevents in response to one or more rules being satisfied. Securityservice 68H may store data indicating the events in audit data 74C.

In the example of FIG. 2, a safety manager may initially configure oneor more safety rules. As such, remote user 24 may provide one or moreuser inputs at computing device 18 that configure a set of safety rulesfor work environments 8A and 8B. For instance, a computing device 60 ofthe safety manager may send a message that defines or specifies thesafety rules. Such message may include data to select or createconditions and actions of the safety rules. PPEMS 6 may receive themessage at interface layer 64 which forwards the message to ruleconfiguration component 681. Rule configuration component 681 may becombination of hardware and/or software that provides for ruleconfiguration including, but not limited to: providing a user interfaceto specify conditions and actions of rules, receive, organize, store,and update rules included in safety rules data store 74E.

Safety rules data store 74E may be a data store that includes datarepresenting one or more safety rules. Safety rules data store 74E maybe any suitable data store such as a relational database system, onlineanalytical processing database, object-oriented database, or any othertype of data store. When rule configuration component 681 receives datadefining safety rules from computing device 60 of the safety manager,rule configuration component 681 may store the safety rules in safetyrules data store 74E.

In some examples, storing the safety rules may include associating asafety rule with context data, such that rule configuration component681 may perform a lookup to select safety rules associated with matchingcontext data. Context data may include any data describing orcharacterizing the properties or operation of a worker, workerenvironment, article of PPE, or any other entity. Context data mayinclude any data describing an optical pattern, optical tag, or opticallabel, or associating the optical pattern with (1) a specific PPE, (2) atype of PPE, (3) another optical pattern, and/or (4) a specific worker.Context data of a worker may include, but is not limited to: a uniqueidentifier of a worker, type of worker, role of worker, physiological orbiometric properties of a worker, experience of a worker, training of aworker, time worked by a worker over a particular time interval,location of the worker, or any other data that describes orcharacterizes a worker. Context data of an article of PPE may include,but is not limited to: a unique identifier of the article of PPE; a typeof PPE of the article of PPE; a usage time of the article of PPE over aparticular time interval; a lifetime of the PPE; a component includedwithin the article of PPE; a usage history across multiple users of thearticle of PPE; contaminants, hazards, or other physical conditionsdetected by the PPE, expiration date of the article of PPE; operatingmetrics of the article of PPE; one or more optical patterns embodied onthe article of PPE. Context data for a work environment may include, butis not limited to: a location of a work environment, a boundary orperimeter of a work environment, an area of a work environment, hazardswithin a work environment, physical conditions of a work environment,permits for a work environment, equipment within a work environment,owner of a work environment, responsible supervisor and/or safetymanager for a work environment.

Table 1, shown below, includes a non-limiting set of rules that may bestored to safety rules data store 74E:

TABLE 1 SAFETY RULES Hub shall immediately assert an “Attention Initial”Alert if Visor Position Status is OPEN in current location requiringVisor Open Allow = NO Hub shall immediately assert a “Critical Initial”Alert if Filter Type Status is not equal to Filter Type or no filterfound required by current location Hub shall store all alerts in aqueue. Critical Alerts shall be highest priority in alert queueAttention Alerts shall have secondary priority in alert queue Hub shallimmediately remove an alert from the queue if its conditions causing thealert have been corrected A newly added alert to the alert queue shallbe flagged as “Active”, if it is higher priority than any other alarmsin the queue. A newly added alert to the alert queue shall be flagged as“Active”, if all other alarms in the queue are Acknowledged or Notify Anewly added alert to the alert queue shall be flagged as “Pending” if anActive alert already exists in the queue and the newly added alert islower in priority than the currently Active alert If an Active alert inthe queue is replaced by a new Active alert because of priority, thereplaced alert shall be flagged as “Pending” An active alert shallenable its respective haptic feedback and LED pattern Hub shall assertan Acknowledge event when user presses and releases button within <3seconds. (Button_Tap) Upon an Acknowledge event the Hub shallimmediately flag the currently Active alert as Acknowledged, if anyActive alerts are in the queue. An Acknowledged alert shall disable itsrespective haptic feedback and LED pattern Upon an Acknowledge event theHub shall immediately flag the highest priority Pending alert as Active,if any Pending alerts exist in the queue. Upon an Acknowledge event theHub shall immediately flag the highest priority Acknowledged alert asNotify, if no Active alerts or Pending exist in the queue. A Notifyalert shall disable its respective haptic feedback and enable its LEDpattern Immediate Cloud Updates - Hub shall send safety violationasserted message via Wi-Fi to cloud service immediately upon assertionof alert Immediate Worker Interface Updates - Hub shall send safety ruleviolation alerts asserted message via BLE to Worker Interfaceimmediately upon assertion of alert Immediate Cloud Updates - Hub shallsend safety violation deasserted message via Wi-Fi to cloud serviceimmediately upon deassertion of alert Immediate Worker InterfaceUpdates - Hub shall send safety violation deasserted message via BLE toWorker Interface immediately upon deassertion of alertIt should be understood that the above examples of table 1 are providedfor purposes of illustration only, and that other rules may bedeveloped.

According to aspects of this disclosure, the rules may be used forpurposes of reporting, to generate alerts, or the like. In an examplefor purposes of illustration, worker 10A may be equipped with PPE 13Aand data hub 14A. Data hub 14A may be initially configured with andstore a unique identifier of worker 10A. When initially assigning thePPE 13A and data hub to worker 10A, a computing device operated byworker 10A and/or a safety manager may cause RMRS 68G to store a mappingin work relation data 74F. Work relation data 74F may include mappingsbetween data that corresponds to PPE, workers, and work environments.Work relation data 74F may be any suitable datastore for storing,retrieving, updating and deleting data. RMRS 68G may store a mappingbetween the unique identifier of worker 10A and a unique deviceidentifier of data hub 14A. Work relation data store 74F may also map aworker to an environment.

Worker 10A may initially put on PPE 13A and data hub 14A prior toentering environment 8A. As worker 10A approaches environment 8A and/orhas entered environment 8A, data hub 14A may determine that worker 10Ais within a threshold distance of entering environment 8A or has enteredenvironment 8A. Data hub 14A may determine that it is within a thresholddistance of entering environment 8A or has entered environment 8A andsend a message that includes context data to PPEMS 6 that indicates datahub 14A is within a threshold distance of entering environment 8A.

PPEMS 6 may additionally or alternatively apply analytics to predict thelikelihood of a safety event. As noted above, a safety event may referto activities of a worker 10 using PPE 13, a condition of PPE 13, or ahazardous environmental condition (e.g., that the likelihood of a safetyevent is relatively high, that the environment is dangerous, that a PPE13 is malfunctioning, that one or more components of the PPE should berepaired or replaced, or the like). For example, PPEMS 6 may determinethe likelihood of a safety event based on application of usage data fromPPE 13 to historical data and models 74B. That is, PPEMS 6 may applyhistorical data and models 74B to usage data from PPE 13 in order tocompute assertions, such as anomalies or predicted occurrences ofimminent safety events based on environmental conditions or behaviorpatterns of a worker using a PPE 13.

PPEMS 6 may apply analytics to identify relationships or correlationsbetween sensed data from PPE 13, environmental conditions of environmentin which PPE 13 is located, a geographic region in which PPE 13 arelocated, and/or other factors. PPEMS 6 may determine, based on the dataacquired across populations of workers 10, which particular activities,possibly within certain environment or geographic region, lead to, orare predicted to lead to, unusually high occurrences of safety events.PPEMS 6 may generate alert data based on the analysis of the usage dataand transmit the alert data to PPEs 13 and/or hubs 14. Hence, accordingto aspects of this disclosure, PPEMS 6 may determine usage data of PPEs13, generate status indications, determine performance analytics, and/orperform prospective/preemptive actions based on a likelihood of a safetyevent.

For example, according to aspects of this disclosure, pattern service68J may generate usage data for PPE 13 using the optical patternidentification and spatial relation techniques described herein. Forexample, PPEMS 6 may determine, based on streams of spatial relationdata for one or more optical patterns associated with a PPE 13, a lengthof time that one or more components have been in use, an instantaneousvelocity or acceleration of worker 10 (e.g., based on an accelerometerincluded in PPE 13 or hubs 14), location(s) of worker 10, a number oftimes or frequency with which a worker 10 has performed a self-check ofPPE 13 or other PPE, a number of times and lengths of times a visor orother component of PPE 13 has been placed into active or standbyposition, or the like.

According to aspects of this disclosure, PPEMS 6 may use the usage datato characterize activity of worker 10. For example, PPEMS 6 mayestablish patterns of productive and nonproductive time (e.g., based onoperation of PPE 13 and/or movement of worker 10), categorize workermovements, identify key motions, and/or infer occurrence of key events.That is, PPEMS 6 may obtain the usage data, analyze the usage data usingservices 68 (e.g., by comparing the usage data to data from knownactivities/events), and generate an output based on the analysis.

The usage statistics may be used to provide an understanding how PPE 13are used by workers 10 to product developers in order to improve productdesigns and performance. In still other examples, the usage statisticsmay be used to gather human performance metadata to develop productspecifications. In still other examples, the usage statistics may beused as a competitive benchmarking tool. For example, usage data may becompared between customers of PPE 13 to evaluate metrics (e.g.productivity, compliance, or the like) between entire populations ofworkers outfitted with PPE 13.

Additionally or alternatively, according to aspects of this disclosure,spatial relation data may be used to assess performance of worker 10wearing a PPE 13. For example, PPEMS 6 may, based on spatial relationdata, recognize motion that may indicate a pending fall by worker 10(e.g., by determining a movement between an optical pattern embodied onthe PPE 13 and another optical pattern in environment 8). In someinstances, PPEMS 6 may, based on spatial relation data, infer that afall has occurred or that worker 10 is incapacitated. PPEMS 6 may alsoperform fall data analysis after a fall has occurred and/or determinetemperature, humidity and other environmental conditions as they relateto the likelihood of safety events.

As another example, PPEMS 6 may, based on spatial relation data,recognize motion that may indicate fatigue or impairment of worker 10.For example, PPEMS 6 may apply spatial relation data from PPE 13 to asafety model that characterizes a motion of a worker 10. In thisexample, PPEMS 6 may determine that the motion of a worker 10 over atime period is anomalous for the worker 10 or a population of workers 10using a PPE 13.

Additionally or alternatively, according to aspects of this disclosure,usage data from PPE 13 may be used to determine alerts and/or activelycontrol operation of PPE 13. For example, PPEMS 6 may determine that asafety condition is present. PPEMS 6 may send data to PPE 13 to changean operating condition of PPE 13. In an example for purposes ofillustration, PPEMS 6 may apply usage data to a safety model thatcharacterizes an expenditure of a filter of one of PPE 13. In thisexample, PPEMS 6 may determine that the expenditure is higher than anexpected expenditure for an environment, e.g., based on conditionssensed in the environment, usage data gathered from other workers 10 inthe environment, or the like. PPEMS 6 may generate and transmit an alertto worker 10 that indicates that worker 10 should leave the environment.

PPEMS 6 may generate, in some examples, a warning when worker 10 is neara hazard in one of environments 8 (e.g., based on spatial relationdata).

Again, PPEMS 6 may determine the above-described performancecharacteristics and/or generate the alert data based on application ofthe spatial relation data to one or more safety models thatcharacterizes activity of a user of a type of PPE 13. The safety modelsmay be trained based on historical data or known safety events. However,while the determinations are described with respect to PPEMS 6, asdescribed in greater detail herein, one or more other computing devices,such as hubs 14 or PPE 13 may be configured to perform all or a subsetof such functionality.

In some instances, PPEMS 6 may apply analytics for combinations of PPE.For example, PPEMS 6 may draw correlations between users of PPE 13and/or the other PPE (such as fall protective equipment, head protectiveequipment, hearing protective equipment, or the like) that is used withPPE 13. That is, in some instances, PPEMS 6 may determine the likelihoodof a safety event based not only on spatial relation and or usage datafrom PPE 13, but also from data for other PPE being used with PPE 13. Insuch instances, PPEMS 6 may include one or more safety models that areconstructed from data of known safety events from one or more devicesother than PPE 13 that are in use with PPE 13.

In general, while certain techniques or functions are described hereinas being performed by certain components, e.g., PPEMS 6, PPE 13, or hubs14, it should be understood that the techniques of this disclosure arenot limited in this way. That is, certain techniques described hereinmay be performed by one or more of the components of the describedsystems. For example, in some instances, PPE 13 may have a limited or nosensor set and/or processing power. In such instances, one or more of ofhubs 14 and/or PPEMS 6 may responsible for most or all of the processingof usage data, determining the likelihood of a safety event, and thelike. In other examples, PPE 13 and/or hubs 14 may have additionalsensors, additional processing power, and/or additional memory, allowingfor PPE 13 and/or hubs 14 to perform additional techniques.Determinations regarding which components are responsible for performingtechniques may be based, for example, on processing costs, financialcosts, power consumption, or the like.

FIG. 3 is a block diagram of a personal protective equipment managementsystem, according to techniques described herein. Computing system 300of FIG. 3 is described below as an example or alternate implementationof PPEMS 6 of FIGS. 1-2. Other examples may be used or may beappropriate in some instances. Although computing system 300 may be astand-alone device, computing system 300 may take many forms, and maybe, or may be part of, any component, device, or system that includes aprocessor or other suitable computing environment for processinginformation or executing software instructions. In some examples,computing system 300, or components thereof, may be fully implemented ashardware in one or more devices or logic elements. Computing system 300may represent multiple computing servers operating as a distributedsystem to perform the functionality described with respect to a PPEMS 6.

Computing system 300 may include one or more communication units 302,one or more input devices 304, one or more output devices 306, powersource 310, one or more processors 312, and one or more storage devices320. One or more storage devices 320 may store user interface module325, application layer services 326 including pattern service 328,optical pattern code to PPE mapping structure 330 and PPE safetyconditions structure 332. One or more of the devices, modules, storageareas, or other components of computing system 300 may be interconnectedto enable inter-component communications (physically, communicatively,and/or operatively). In some examples, such connectivity may be providedby through system bus, a network connection, an inter-processcommunication data structure, or any other method for communicatingdata.

Power source 310 may provide power to one or more components ofcomputing system 300. In some examples, power source 310 may be abattery. In other examples, power source 310 may receive power from theprimary alternative current (AC) power supply in a building, home, orother location. In still further examples, computing system 300 and/orpower source 310 may receive power from another source.

One or more input devices 304 of computing system 300 may generate,receive, or process input. Such input may include input from a keyboard,pointing device, voice responsive system, video camera, biometricdetection/response system, button, sensor, mobile device, control pad,microphone, presence-sensitive screen, network, or any other type ofdevice for detecting input from a human or machine. One or more outputdevices 306 of computing system 300 may generate, transmit, or processoutput. Examples of output are tactile, audio, visual, and/or videooutput. Output devices 306 may include a display, sound card, videographics adapter card, speaker, presence-sensitive screen, one or moreUSB interfaces, video and/or audio output interfaces, or any other typeof device capable of generating tactile, audio, video, or other output.Output devices 306 may include a display device, which may function asan output device using technologies including liquid crystal displays(LCD), quantum dot display, dot matrix displays, light emitting diode(LED) displays, organic light-emitting diode (OLED) displays, cathoderay tube (CRT) displays, e-ink, or monochrome, color, or any other typeof device for generating tactile, audio, and/or visual output. In someexamples, computing system 300 may include a presence-sensitive displaythat may serve as a user interface device that operates both as one ormore input devices 304 and one or more output devices 306.

One or more communication units 302 of computing system 300 maycommunicate with devices external to computing system 300 bytransmitting and/or receiving data, and may operate, in some respects,as both an input device and an output device. In some examples,communication unit 302 may communicate with other devices over anetwork, e.g., image capture device 28 (or a storage device storingimages generated by image capture device 28), computing devices 60, hubs14, some instances of PPEs 13, and/or safety stations 15. In otherexamples, one or more communication units 302 may send and/or receiveradio signals on a radio network such as a cellular radio network. Inother examples, one or more communication units 302 may transmit and/orreceive satellite signals on a satellite network such as a GlobalPositioning System (GPS) network. Examples of one or more communicationunits 302 may include a network interface card (e.g. such as an Ethernetcard), an optical transceiver, a radio frequency transceiver, a GPSreceiver, or any other type of device that can send and/or receiveinformation. Other examples of one or more communication units 302 mayinclude Bluetooth®, GPS, 3G, 4G, and Wi-Fi® radios found in mobiledevices as well as Universal Serial Bus (USB) controllers and the like.

One or more processors 312 of computing system 300 may implementfunctionality and/or execute instructions associated with computingsystem 300. Examples of one or more processors 312 may includemicroprocessors, application processors, display controllers, auxiliaryprocessors, one or more sensor hubs, and any other hardware configuredto function as a processor, a processing unit, or a processing device.Computing system 300 may use one or more processors 312 to performoperations in accordance with one or more aspects of the presentdisclosure using software, hardware, firmware, or a mixture of hardware,software, and firmware residing in and/or executing at computing system300.

One or more storage devices 320 within computing system 300 may storeinformation for processing during operation of computing system 300. Insome examples, one or more storage devices 320 are temporary memories,meaning that a primary purpose of the one or more storage devices is notlong-term storage. One or more storage devices 320 on computing system300 may be configured for short-term storage of information as volatilememory and therefore not retain stored contents if deactivated. Examplesof volatile memories may include random access memories (RAM), dynamicrandom-access memories (DRAM), static random-access memories (SRAM), andother forms of volatile memories known in the art. One or more storagedevices 320, in some examples, also include one or morecomputer-readable storage media. One or more storage devices 320 may beconfigured to store larger amounts of information than volatile memory.One or more storage devices 320 may further be configured for long-termstorage of information as non-volatile memory space and retaininformation after activate/off cycles. Examples of non-volatile memoriesmay include magnetic hard disks, optical discs, floppy disks, flashmemories, or forms of electrically programmable memories (EPROM) orelectrically erasable and programmable (EEPROM) memories. One or morestorage devices 320 may store program instructions and/or dataassociated with one or more of the modules described in accordance withone or more aspects of this disclosure.

One or more processors 312 and one or more storage devices 320 mayprovide an operating environment or platform for one or one moremodules, which may be implemented as software, but may in some examplesinclude any combination of hardware, firmware, and software. One or moreprocessors 312 may execute instructions and one or more storage devices320 may store instructions and/or data of one or more modules. Thecombination of one or more processors 312 and one or more storagedevices 320 may retrieve, store, and/or execute the instructions and/ordata of one or more applications, modules, or software. One or moreprocessors 312 and/or one or more storage devices 320 may also beoperably coupled to one or more other software and/or hardwarecomponents, including, but not limited to, one or more of the componentsillustrated in FIG. 3.

One or more modules illustrated in FIG. 3 as being included within oneor more storage devices 320 (or modules otherwise described herein) mayperform operations described using software, hardware, firmware, or amixture of hardware, software, and firmware residing in and/or executingat computing system 300. Computing system 300 may execute each of themodule(s) with multiple processors or multiple devices. Computing system300 may execute one or more of such modules as a virtual machine orcontainer executing on underlying hardware. One or more of such modulesmay execute as one or more services of an operating system or computingplatform. One or more of such modules may execute as one or moreexecutable programs at an application layer of a computing platform.

One or more storage devices 320 stores optical pattern code to PPEmapping structure 330, a data structure that maps optical pattern codesto PPEs 13 having the codes embodied thereon. PPEs 13 may be identifiedusing unique identifiers or by a type of PPE, for instance. In someexamples, structure 330 maps pairs of optical pattern codes to PPEs 13having at least one of the optical pattern codes embodied thereon.Structure 330 is an associative data structure and may represent, e.g.,a database, table, list, or map.

One or more storage device 320 stores PPE safety conditions 332. PPEsafety conditions include a list of rules defining safety conditionsidentifiable by spatial relations between pairs of optical patterns forPPEs 13 having at least one of the optical patterns embodied thereon.PPE safety conditions 332 may be implemented using a database, a list, afile, or other structure. PPE safety conditions 332 may be included inor an example of safety rules data store 74E of FIG. 2.

User interface (UI) module 325 for execution by processors 312 outputs,for display via output device(s) 306, a user interface to enable anoperator to configure structures 330, 332. Input device(s) 304 receiveuser input including configuration data for optical pattern code to PPEmapping 330 and PPE safety conditions 332. User interface 325 processesthe configuration data and updates the structures 330, 332 using theconfiguration data.

Application layer services 326 may represent an example instance ofservices 68 of FIG. 2. Pattern service 328 may represent an exampleinstance of pattern service 68J of FIG. 2. Pattern service 328 forexecution by processors 312 may output, via communication unit(s) 302,commands to read or otherwise obtain images 27 generated by imagecapture device 28. Pattern service 328 may temporarily store, to storagedevice(s) 320, a subset of images 27 for processing.

Pattern service 328 processes one or more images 27 to identify anddetermine a spatial relation between a pair of optical patterns in theone or more images. Pattern service 328 may apply image processingtechniques to determine a spatial relation between the pair of opticalpatterns. For example, pattern service 328 may process the one or moreimages to determine orientations of each of the optical patterns in theone or more images and determine a relative orientation between the pairof optical patterns. As another example, pattern service 328 may useknown dimensions for each of the optical patterns, as well as imagecapture properties of image capture device 28, to determine based on theone or more images 27 a distance between the pair of optical patterns.

Pattern service 328 may query a dataset of optical patterns to look upthe optical pattern codes for the pair of optical patterns or,alternatively, pattern service 328 may derive the optical pattern codesfrom encodings embedded in the optical patterns. Based on opticalpattern codes for the pair of optical patterns, pattern service 328looks up an optical pattern code to PPE mapping in structure 330 and,using the mapping, maps at least one of the optical pattern codes to aPPE to identify a PPE 13 or type of PPE 13 having at least one of theoptical patterns embodied thereon.

Based on this identification, pattern service 328 looks up a PPE safetycondition for the identified PPE 13 or type of PPE 13 in PPE safetyconditions 332. If the PPE safety condition for the identified PPE 13 ortype of PPE 13 is satisfied by the spatial relation between the pair ofoptical patterns in the one or more images, pattern service 328 mayperform an operation, such as storing an event, outputting anotification 332 via communication unit(s) 302, or outputting a commandvia communication unit(s) 302 to control a machine or PPE 13.

FIGS. 4A-4B depict an example of a PPE in an active and standbyposition, the PPE having optical patterns embodied thereon, according totechniques of this disclosure. More specifically, FIGS. 4A-4B depict afiltered air respirator system, which may also be referred to as asupplied air system generally. The system represents one example of PPE13 shown in FIG. 2. The system includes a head top 403 having a helmet400 and a visor 401. Head top 403 is connectable to a clean air supplysource by a hose. Clean air supply source can be any type of air supplysource, such as a blower assembly for a powered air purifying respirator(PAPR), an air tank for a self-contained breathing apparatus (SCBA) orany other device that provides air to head top 403.

Visor 401 is sized to fit over at least a user's nose and mouth. Visor401 includes a lens which is rotatable attached to helmet 400 at a pivotpoint. A rotation position of visor 401 about the pivot point determineswhether the visor 401 is open, partially open, or closed. A closed visor401 provides eye and face protection for hazards as well as respiratoryprotection to a user (provided the air supply to head top 403 issatisfactory). A partially open visor 401 provides at least some eye andface protection for hazards as well as at least some amount ofrespiratory protection. This “partially open” visor state, if kept toshort durations, can assist the user in face to face communications withother workers. An open visor 401 provides little or no protection.

Helmet 400 has an optical pattern 402 embodied thereon. Visor 401 has anoptical pattern 404 embodied thereon. In some examples, each side of thevisor 401 has an optical pattern embodied thereon, which may be the sameoptical pattern. In this way, at least one of these optical patterns maybe visible to an image capture device in more orientations of the workerwearing the head top 403. Optical patterns 402, 404 may be printed onrespective optical tags affixed to helmet 400 and visor 401,respectively.

FIG. 4A depicts visor 401 in a closed position that is the activeposition for the head top 403. When worn by a worker in a workenvironment, an image capture device 28 may obtain an image showing thehead top 403 having visor 401 in the closed position. PPEMS 6 may obtainand process the image to determine a spatial relation between opticalpatterns 402, 404. More particularly, in this example of a PPE, PPEMS 6may determine an orientation of optical pattern 402, an orientation ofoptical pattern 404, and a relative orientation between optical patterns402, 404 that corresponds to a difference between the two orientationsthereof. The relative orientation determined by PPEMS 6 indicates thehead top 403 has visor 401 in a closed position. The closed position isthe active position for head top 403 and may not correspond to a safetycondition. However, PPEMS 6 may store event data having (1) the image,(2) a description of the head top 403 or full respirator system, (3) anidentification of the worker, (4) a description of the spatial relationbetween optical patterns 402, 404, (5) a time of the image capture ofthe image, and/or (6) an indication that no safety condition waspresent, for instance.

FIG. 4B depicts visor 401 in an open position that is the standbyposition for head top 403. When worn by a worker in a work environment,visor 401 may be rotated about the pivot by the worker, and an imagecapture device 28 may contemporaneously obtain an image showing head top403 having visor 401 in the open position. PPEMS 6 may obtain andprocess the image to determine a spatial relation between opticalpatterns 402, 404. More particularly, in this example of a PPE, PPEMS 6may determine an orientation of optical pattern 402, an orientation ofoptical pattern 404, and a relative orientation between optical patterns402, 404 that corresponds to a difference between the two orientationsthereof. The relative orientation determined by PPEMS 6 indicates thehead top 403 has visor 401 in an open position. The relative orientationis different than then relative orientation as in the closed positiondepicted in FIG. 4A. The open position is the standby position for headtop 403 and may correspond to a safety condition for head top 403operating in the work environment. PPEMS 6 may therefore perform anoperation based at least in part on the safety condition. PPEMS 6 mayalso store event data having (1) the image, (2) a description of thehead top 403 or full respirator system, (3) an identification of theworker, (4) a description of the spatial relation between opticalpatterns 402, 404, (5) a time of the image capture of the image, and/or(6) an indication that the safety condition occurred, for instance.

FIGS. 5A-5C depict an example of a PPE in active and standby positions,the PPE having optical patterns embodied thereon, according totechniques of this disclosure. More specifically, FIGS. 5A-5C depict anoise attenuation system, in accordance with techniques describedherein. The noise attenuation system 503 represents one example of PPE13 shown in FIG. 2. The noise attenuation system 503 includes a helmet500 and ear muffs 501. Ear muffs 501 are sized to fit over a user'sears. Ear muffs 501 are rotatable attached to helmet 500 at a pivotpoint. A rotation position of ear muffs 501 about the pivot pointdetermines whether the ear muffs 501 are in active or standby position.Ear muffs 501 in active position (i.e., positioned to enclose the ears)provide noise attenuation to the ears of a user. Ear muffs 501 instandby position do not provide noise attenuation to the ears of a user.

Helmet 500 has an optical pattern 502 embodied thereon. Ear muffs 501have an optical pattern 504 embodied thereon. In some examples, eachside of the ear muffs 501 have an optical pattern embodied thereon,which may be the same optical pattern. In this way, at least one ofthese optical patterns may be visible to an image capture device in moreorientations of the worker wearing the system 503. Optical patterns 502,504 may be printed on respective optical tags affixed to helmet 500 andear muffs 501, respectively.

FIG. 5A depicts ear muffs 501 in the active position for system 503.When worn by a worker in a work environment, an image capture device 28may obtain an image showing system 503 having ear muffs 501 in theactive position. PPEMS 6 may obtain and process the image to determine aspatial relation between optical patterns 502, 504. More particularly,in this example of a PPE, PPEMS 6 may determine an orientation ofoptical pattern 502, an orientation of optical pattern 504, and arelative orientation between optical patterns 502, 504 that correspondsto a difference between the two orientations thereof. The relativeorientation determined by PPEMS 6 indicates the system 503 has ear muffs501 in an active position. The active position may not correspond to asafety condition. However, PPEMS 6 may store event data having (1) theimage, (2) a description of the system 503, (3) an identification of theworker, (4) a description of the spatial relation between opticalpatterns 502, 504, (5) a time of the image capture of the image, and/or(6) an indication that no safety condition was present, for instance.

FIG. 5B depicts ear muffs 501 in an open position that is the standbyposition for system 503. When worn by a worker in a work environment,ear muffs 501 may be rotated about the pivot by the worker, and an imagecapture device 28 may contemporaneously obtain an image showing system503 having ear muffs 501 in the standby position. PPEMS 6 may obtain andprocess the image to determine a spatial relation between opticalpatterns 502, 504. More particularly, in this example of a PPE, PPEMS 6may determine an orientation of optical pattern 502, an orientation ofoptical pattern 504, and a relative orientation between optical patterns502, 504 that corresponds to a difference between the two orientationsthereof. The relative orientation determined by PPEMS 6 indicates thesystem 503 has ear muffs 501 in a standby position. The relativeorientation is different than then relative orientation as in the activeposition depicted in FIG. 5A. The standby position may correspond to asafety condition for system 503 operating in the work environment. PPEMS6 may therefore perform an operation based at least in part on thesafety condition. PPEMS 6 may also store event data having (1) theimage, (2) a description of the system 503, (3) an identification of theworker, (4) a description of the spatial relation between opticalpatterns 502, 504, (5) a time of the image capture of the image, and/or(6) an indication that the safety condition occurred, for instance.

FIG. 5C depicts helmet 500 without attached ear muffs 501. In thissituation, only optical pattern 502 is embodied on a component of system503. PPEMS 6 may obtain and process an image of system 503 to determineoptical pattern 502 is present and optical pattern 504 is not present.Optical patterns 502, 504 are associated as a pair of optical patternsin PPEMS 6. Because optical pattern 504 is not present for system 503,ear muffs 501 are not present, which is a configuration that maycorrespond to a safety condition for system 503 operating in the workenvironment. PPEMS 6 may therefore perform an operation based at leastin part on the safety condition. PPEMS 6 may also store event datahaving (1) the image, (2) a description of the system 503, (3) anidentification of the worker, (4) a description of the absence of theexpected optical pattern 504, (5) a time of the image capture of theimage, and/or (6) an indication that the safety condition occurred, forinstance.

In some examples of a noise attenuation system including a helmet andear muffs, the ear muffs may include an “over-the-head” tension band forholding the ear muffs to the user's ears. The tension band may bepositioned under the helmet, around the helmet, or in the back of theuser's head. Nevertheless, in such cases, ear muffs 501 in the activeposition enclose the user's ears to provide noise attenuation, and PPEMS6 may apply techniques described above to determine the spatial relationbetween optical patterns 502, 504 and identify whether a safetycondition is present.

FIGS. 6A-6B depict an example of a PPE and a machine, each having anoptical pattern embodied thereon, according to techniques of thisdisclosure. More specifically, FIGS. 6A-6B depict a worker wearing thefiltered air respirator system of FIGS. 4A-4B, and a machine. The workeris wearing head-top 403 with visor 401 positioned in the closedposition, which provides face, eye, and/or respiratory protection.Machine 600 may be located in a work environment and present one or moreproximity hazards, such as those associated with force-induced trauma,lacerations, heat, noxious gases, falls, noise, and so forth. Machine600 may be, to name just a few examples, a welding system, saw or othercutting tool, or jackhammer. Machine 600 may be an example of item 26 ofFIG. 1.

FIG. 6A depicts the worker at a distance 604A from machine 600. FIG. 6Bdepicts the worker at a distance 604B from machine 600, where distance604B is shorter than distance 604A.

Machine 600 has optical pattern 602 embodied thereon. PPEMS 6 may obtainand process an image that includes optical patterns 402, 602 as shown inFIG. 6A to determine a spatial relation between optical patterns 402,602. More particularly, in this example of a PPE paired with a machinein PPEMS 6 by the pairing of optical patterns 402, 602, PPEMS 6 maydetermine a distance between optical patterns 402, 602 corresponding todistance 604A. The spatial relation determined by PPEMS 6 indicates thatthe user is not within a threshold distance for the proximity hazardsassociated with machine 600. This distance may not correspond to asafety condition. PPEMS 6 may further determine a spatial relationbetween optical patterns 402, 404, as described above with respect toFIGS. 4A-4B, to determine visor 401 is in an open position in somecases. PPEMS 6 may responsively store event data having (1) the image,(2) a description of the system 403 and machine 600, (3) anidentification of the worker, (4) a description of the spatial relationbetween optical patterns 402, 602 (5) a description of the spatialrelation between optical patterns 402, 404 (6) a time of the imagecapture of the image, and/or (7) an indication that no safety conditionwas present, for instance.

PPEMS 6 may, at a subsequent time in which the worker has moved to adistance 604B to machine 600, obtain and process an image that includesoptical patterns 402, 602 as shown in FIG. 6B to determine a spatialrelation between optical patterns 402, 602. More particularly, in thisexample of a PPE paired with a machine in PPEMS 6 by the pairing ofoptical patterns 402, 602, PPEMS 6 may determine a distance betweenoptical patterns 402, 602 corresponding to distance 604B. The spatialrelation determined by PPEMS 6 indicates that the user is within athreshold distance for the proximity hazards associated with machine600. This distance may correspond to a safety condition. PPEMS 6 mayfurther determine a spatial relation between optical patterns 402, 404,as described above with respect to FIGS. 4A-4B, to determine visor 401is in an open position. PPEMS 6 may determine that the open position ofvisor 401 in combination with the worker being within the thresholddistance for the proximity hazards associated with machine 600, asindicated by the spatial relation between optical patterns 402, 602,corresponds to a safety condition. PPEMS 6 may therefore perform anoperation based at least in part on the safety condition. PPEMS 6 mayalso store event data having (1) the image, (2) a description of thesystem 403 and machine 600, (3) an identification of the worker, (4) adescription of the spatial relation between optical patterns 402, 602(5) a description of the spatial relation between optical patterns 402,404 (6) a time of the image capture of the image, and/or (7) anindication that no safety condition was present, for instance.

FIG. 7 is a flowchart illustrating an example mode of operation for apersonal protective equipment management system, according to techniquesdescribed in this disclosure. Mode of operation 700 is described withrespect to PPEMS 6 in the context of FIG. 1 but may be performed by anyPPEMS described herein or other suitable components.

PPEMS 6 receives first configuration data that creates an associationbetween a first optical pattern 22A and a second optical pattern 23A(702). The association may be between respective optical pattern codesfor the first optical pattern 22A and the second optical pattern 23A.PPEMS 6 receives second configuration data that defines a safetycondition that is conditioned on a spatial relation between the firstoptical pattern 22A and the second optical pattern 23A (703). Forexample, the second configuration data may specify that the safetycondition is present if the spatial relation is within a threshold.

PPEMS 6 subsequently obtains an image of a work environment, captured byimage capture device 28 (740). PPEMS 6 processes the image to identifyfirst optical pattern 22A in the image, the first optical pattern 22Abeing embodied on an article of PPE 13A (705). PPEMS 6 determines, basedat least on the first configuration data, that second optical pattern23A is associated with the first optical pattern 22A (706). Based atleast on the association and on the image, and the images of the firstoptical pattern 22A and the second optical pattern 23A identifiedtherein, PPEMS 6 determines a spatial relation between the first opticalpattern 22A and the second optical pattern 23A (708). Operations 708 maybe performed before operation 706.

If the spatial relation satisfies a condition of the safety conditionspecified in the second configuration data (YES branch of 710), thesafety condition is present and PPEMS 6 performs an operation based onthe safety condition (712). If the spatial relation does not satisfy acondition of the safety condition specified in the second configurationdata (NO branch of 710), the PPEMS 6 may take no ameliorative action.

Optical patterns 22 can be formed using printing or patterning. Forexample, the optical patterns 22 may be formed using inkjet printing,screen printing, flexographic printing, and the like onto a substrate.Optical patterns 22 may be die cut onto a substrate, or it can be etchedonto a substrate. Optical patterns 22 may be embedded on the PPE bydirect directly printing or etching the PPE surface, or optical patterns22 may be applied to the PPE in the form of a label. The label can beaffixed on the PPE by adhesive or by means of mechanical fasteners forexample.

The substrate can be any printable or patternable material such aspaper, plastic film, tape or retroreflective material. A retroreflectivesubstrate may be beaded such as 3M engineer grade retroreflectivesheeting series 3200, 3M™ Scotchlite™ High Visibility Reflective tapeseries 8910, or it can be prismatic such as 3M™ High Intensity PrismaticReflective Sheeting Series 3930, and 3M™ High Definition ReflectiveLicense Plate Sheeting Series 6700. For descriptive purposes only, the3M™ High Definition Reflective License Plate Sheeting will be used insubsequent examples to describe tags according to techniques herein.

FIGS. 8A-8B illustrate cross-sectional views of portions of an opticalpattern formed on a retroreflective sheet, in accordance with one ormore techniques of this disclosure. Retroreflective article 800 includesa retroreflective layer 810 including multiple cube corner elements 812that collectively form a structured surface 814 opposite a major surface816. The optical elements can be full cubes, truncated cubes, orpreferred geometry (PG) cubes as described in, for example, U.S. Pat.No. 7,422,334, incorporated herein by reference in its entirety. Thespecific retroreflective layer 810 shown in FIGS. 8A-8B includes a bodylayer 818, but those of skill will appreciate that some examples do notinclude an overlay layer. One or more barrier layers 834 are positionedbetween retroreflective layer 810 and conforming layer 832, creating alow refractive index area 838. Barrier layers 834 form a physical“barrier” between cube corner elements 812 and conforming layer 832.Barrier layer 834 can directly contact or be spaced apart from or canpush slightly into the tips of cube corner elements 812. Barrier layers834 have a characteristic that varies from a characteristic in one of(1) the areas 832 not including barrier layers (view line of light ray850) or (2) another barrier layer 834. Exemplary characteristicsinclude, for example, color and infrared absorbency.

In general, any material that prevents the conforming layer materialfrom contacting cube corner elements 812 or flowing or creeping into lowrefractive index area 838 can be used to form the barrier layerExemplary materials for use in barrier layer 834 include resins,polymeric materials, dyes, inks (including color-shifting inks), vinyl,inorganic materials, UV-curable polymers, multi-layer optical films(including, for example, color-shifting multi-layer optical films),pigments, particles, and beads. The size and spacing of the one or morebarrier layers can be varied. In some examples, the barrier layers mayform a pattern on the retroreflective sheet. In some examples, one maywish to reduce the visibility of the pattern on the sheeting. Ingeneral, any desired pattern can be generated by combinations of thedescribed techniques, including, for example, indicia such as letters,words, alphanumerics, symbols, graphics, logos, or pictures. Thepatterns can also be continuous, discontinuous, monotonic, dotted,serpentine, any smoothly varying function, stripes, varying in themachine direction, the transverse direction, or both; the pattern canform an image, logo, or text, and the pattern can include patternedcoatings and/or perforations. The pattern can include, for example, anirregular pattern, a regular pattern, a grid, words, graphics, imageslines, and intersecting zones that form cells.

The low refractive index area 838 is positioned between (1) one or bothof barrier layer 834 and conforming layer 832 and (2) cube cornerelements 812. The low refractive index area 838 facilitates totalinternal reflection such that light that is incident on cube cornerelements 812 adjacent to a low refractive index area 838 isretroreflected. As is shown in FIG. 8B, a light ray 850 incident on acube corner element 812 that is adjacent to low refractive index layer838 is retroreflected back to viewer 802. For this reason, an area ofretroreflective article 800 that includes low refractive index layer 838can be referred to as an optically active area. In contrast, an area ofretroreflective article 800 that does not include low refractive indexlayer 838 can be referred to as an optically inactive area because itdoes not substantially retroreflect incident light. As used herein, theterm “optically inactive area” refers to an area that is at least 50%less optically active (e.g., retroreflective) than an optically activearea. In some examples, the optically inactive area is at least 40% lessoptically active, or at least 30% less optically active, or at least 20%less optically active, or at least 10% less optically active, or atleast at least 5% less optically active than an optically active area.

Low refractive index layer 838 includes a material that has a refractiveindex that is less than about 1.30, less than about 1.25, less thanabout 1.2, less than about 1.15, less than about 1.10, or less thanabout 1.05. In general, any material that prevents the conforming layermaterial from contacting cube corner elements 812 or flowing or creepinginto low refractive index area 838 can be used as the low refractiveindex material. In some examples, barrier layer 834 has sufficientstructural integrity to prevent conforming layer 832 from flowing into alow refractive index area 838. In such examples, low refractive indexarea may include, for example, a gas (e.g., air, nitrogen, argon, andthe like). In other examples, low refractive index area includes a solidor liquid substance that can flow into or be pressed into or onto cubecorner elements 812. Example materials include, for example, ultra-lowindex coatings (those described in PCT Patent Application No.PCT/US2010/031290), and gels.

The portions of conforming layer 832 that are adjacent to or in contactwith cube corner elements 812 form non-optically active (e.g.,non-retroreflective) areas or cells. In some examples, conforming layer832 is optically opaque. In some examples conforming layer 832 has awhite color.

In some examples, conforming layer 832 is an adhesive. Example adhesivesinclude those described in PCT Patent Application No. PCT/US2010/031290.Where the conforming layer is an adhesive, the conforming layer mayassist in holding the entire retroreflective construction togetherand/or the viscoelastic nature of barrier layers 834 may prevent wettingof cube tips or surfaces either initially during fabrication of theretroreflective article or over time.

In some examples, conforming layer 832 is a pressure sensitive adhesive.The PSTC (pressure sensitive tape council) definition of a pressuresensitive adhesive is an adhesive that is permanently tacky at roomtemperature which adheres to a variety of surfaces with light pressure(finger pressure) with no phase change (liquid to solid). While mostadhesives (e.g., hot melt adhesives) require both heat and pressure toconform, pressure sensitive adhesives typically only require pressure toconform. Exemplary pressure sensitive adhesives include those describedin U.S. Pat. No. 6,677,030. Barrier layers 834 may also prevent thepressure sensitive adhesive from wetting out the cube corner sheeting.In other examples, conforming layer 832 is a hot-melt adhesive.

In some examples, a pathway article may use a non-permanent adhesive toattach the article message to the base surface. This may allow the basesurface to be re-used for a different article message. Non-permanentadhesive may have advantages in areas such as roadway construction zoneswhere the vehicle pathway may change frequently.

In the example of FIG. 8A, a non-barrier region 835 does not include abarrier layer, such as barrier layer 834. As such, light may reflectwith a lower intensity than barrier layers 834A-834B. Different patternsof non-barrier regions 835 and barrier layers 834A-834B on differentinstances of retroreflective article 800 may define the optical patternsdescribed and used herein.

Additional example implementations of a retroreflective article forembodying an optical pattern are described in U.S. patent applicationSer. No. 14/388,082, filed Mar. 29, 2013, which is incorporated byreference herein in its entirety. Additional description is found inU.S. Provisional Appl. Nos. 62/400,865, filed Sep. 28, 2016; 62/485,449,filed Apr. 14, 2017; 62/400,874, filed Sep. 28, 2016; 62/485,426, filedApr. 14, 2017; 62/400,879, filed Sep. 28, 2016; 62/485,471, filed Apr.14, 2017; and 62/461,177, filed Feb. 20, 2017; each of which isincorporated herein by reference in its entirety.

FIG. 9 is a data structure, usable by a PPEMS, for identifying a safetycondition in accordance with techniques described herein. Table 900 mayrepresent an example instance of optical pattern code to PPE mappingstructure 330. Entries of table 900 map a pair of optical pattern codesto a PPE pairing, where the PPE pairing may be a pairing of twocomponents of an article of PPE, two articles of PPE, an article of PPEand an item in a work environment. In the illustrated example, opticalpattern codes are shown as 5-digit numbers, but other examples ofoptical pattern codes may be used. The optical pattern codes may beexamples of identifiers corresponding to machine-readable codes foroptical patterns, as described above.

PPEMS 6 may determine a pair of optical patterns present in an obtainedimage and determine the respective optical pattern codes for the pair.PPEMS 6 may then query table 900 to determine the equipment pairingassociated with the pair of optical patterns. For example, opticalpattern code pair 00001, 00002 are for a pair of optical patternsembodied on a helmet and a visor, respectively, such as helmet 400 andvisor 401 of FIGS. 4A-4B.

In some examples, a pair of optical patterns are the same opticalpattern having a same optical pattern code (or “identifier”). In suchcases, the optical pattern code pair may instead be a single opticalpattern code for the pair of same optical patterns.

FIG. 10 is a data structure, usable by a PPEMS, for identifying a safetycondition in accordance with techniques described herein. Table 1000 mayrepresent an example instance of PPE safety conditions 332. Each entryof table 1000 maps an equipment pairing to a safety condition and anoperation to be performed if the safety condition is satisfied/present.The safety condition is based on a spatial relation between a pair ofoptical patterns.

PPEMS 6 may use table 1000 in conjunction with table 900 to determinewhether a safety condition is present and, if so, to perform anoperation. For example, PPEMS 6 may determine a pair of optical patternspresent in an obtained image and determine the respective opticalpattern codes for the pair. PPEMS 6 may then query table 900 todetermine the equipment pairing associated with the pair of opticalpatterns. For example, optical pattern code pair 00001, 00002 are for apair of optical patterns embodied on a helmet and a visor, respectively.

PPEMS 6 may query table 1000 for the equipment pairing of the helmet andvisor to obtain the safety condition, which in this example is“orientation difference >5 degrees”. PPEMS 6 may determine the spatialrelation and more specifically the relative orientation between the pairof optical patterns having optical pattern codes 00001, 00002 andpresent in an obtained image. If the relative orientation is greaterthan 5 degrees, PPEMS 6 may perform the specified operation, in thiscase, to notify the worker.

Tables 900 and 1000 may be combined in some cases such that each pair ofoptical pattern codes has a corresponding safety condition andoperation, rather than by relation to an equipment pairing. Each pair ofoptical pattern codes may be trained into a combined table as aconfiguration step for a PPE that includes the pair of optical patterncodes. For example, an operator may place a pair of optical tags on thevisor and helmet of a PPE, for instance. PPEMS 6 may obtain an image ofthe pair of optical tags as part of the configuration, with the PPE inactive position. The operator may provide user input indicating the typeof PPE. PPEMS 6 may determine a base relative orientation of the pair ofoptical tags of the PPE, then use the base relative orientation as abasis for subsequently determining the position or operational status ofthe PPE. In the above example, pivoting the visor up by 90 degrees to anopen/standby position modifies the relative orientation of the pair ofoptical patterns of the optical tags by substantially 90 degrees.Accordingly, a safety condition that is conditioned on the relativeorientation between the pair of optical patterns may be configured toaccount for the base relative orientation.

FIG. 11 is an example of an encoding usable for an optical pattern forembodiment on a PPE, according to techniques of this disclosure. Code1100 is a visual representation of an optical pattern code. Code 1100 inthis example is 7 modules (width) by 9 modules (height) but in otherexamples may be expanded or reduced in dimension. Each module or “cell”1107 is colored either white or black (infrared reflecting or absorbing,respectively). A pre-defined set of modules 1107 (labelled as “whitelocation finder” and “black location finder”) are always either white orblack according to a pre-defined pattern, which allows the imageprocessing software of PPEMS 6 to locate and identify that an opticalpattern code is present in an image generated by an image capturedevice. In FIG. 11, white location finders are located at the cornersand “top” of code 1100 and the black location finders are located at the“top” of code 1100. In addition, the set 1106 of modules 1107 that makeup the white and block location finders allow the image processingsoftware to determine an orientation of the code 1100 with respect tothe coordinate system of the image. In FIG. 11, the “top” of code 1100is labeled “TOP” and the bottom is labeled “BOTTOM” to denote that code1100 has an orientation.

The remaining 48 cells are divided into 24 data cells 1102 that givesunique representations based on the black/white assignments for eachcell as well as 24 correction code cells 1104 that allows the code to berecovered even if the code is partially blocked or incorrectly read. Inthis specific design, there are 2{circumflex over ( )}24 uniquerepresentations (˜16 million), but based on the resolution needed, thecode can be expanded to include more data cells 1102 and fewercorrection code cells 1104 (for example, if 12 of the correction codecells 1104 become data cells 1102, there would be 2{circumflex over( )}36 or ˜64 billion unique representations).

In some cases, the code operates as a more generalized version of thecode where a full rectangular retroreflective substrate is available andthe correction code is left fully intact for recovery and verification.The location finder uses all corners of the code and an alternatingwhite/black pattern along the top edge allows for a single system todifferentiate and decode multiple code sizes.

In some examples, code 1100 is printed onto 3M High Definition LicensePlate Sheeting Series 6700 with a black ink using an ultraviolet (UV)inkjet printer, such as MIMAKU UJF-3042HG or 3M′ Precision Plate Systemto produce an optical tag. The ink may contain carbon black as thepigment and be infrared absorptive (i.e., appears black when viewed byan infrared camera). The sheeting includes a pressure-sensitive adhesivelayer that allows the printed tag to be laminated onto articles of PPE.In some examples, the code 1100 is visible to the user. In someexamples, an additional layer of mirror film can be laminated over thesheeting with the printed code 1100, thereby hiding the printed code1100 from the naked eye. As the mirror film is transparent to infraredlight, an infrared camera can still detect the code 1100 behind themirror film, which may also improve image processing precision. Themirror film can also be printed with an ink that is infrared transparentwithout interfering with the ability for an infrared camera to detectthe code 1100.

In some examples, an optical tag may be generated to include one or morelayers that avoid the high reflectivity of a mirror film but be infraredtransparent such that the machine-readable code is not visible inambient light but readily detectable within images obtained by aninfrared camera. This construction may be less distracting to workers orother users.

Such an optical tag can be generated with a white mirror film, such asthose disclosed in PCT/US2017/014031, on top of a retroreflectivematerial. The radiometric properties of the retroreflective light of anoptical tag can be measured with an Ocean Optics Spectrometer (modelnumber FLAME-S-VIS-NIR), light source (model HL-2000-FHSA), andreflectance probe (model QR400-7-VIS-BX) over a geometry of 0.2 degreeobservation angle and 0 degree entrance angle, as shown by percent ofreflectivity (R %) over a wavelength range of 400-1000 nanometers.

Optical tags may be manufactured in pairs such that a first optical tagincludes a first optical pattern and a second optical tag includes asecond optical pattern. The first and second optical patterns may beassociated inherently by indicating the same code/identifier, orexplicitly by configuring PPEMS 6 to include an association of the firstoptical pattern and the second optical pattern. A pair of optical tagswith associated, respective optical patterns may be packaged and soldfor placement upon different components of single PPE or upon differentPPEs for which the spatial relation between the PPEs may indicate asafety condition.

FIG. 12 illustrates a retroreflective spectrum of a 3M™ High DefinitionLicense Plate Sheeting Series 6700 laminated with 3M™ Digital LicensePlate Clear Protective Film Series 9097, in the presence or the absenceof the white mirror film. The white mirror film blocks almost allretroreflective light in the visible wavelength range (i.e., 400nanometer to 700 nanometer), while permitting sufficient infrared (IR)light (including 950 nanometer) through to be captured by an IR camera.

FIGS. 13A-13B depicts optical properties of the example optical tags,according to techniques of this disclosure. For these example opticaltags, a 40 millimeter by 40-millimeter square pattern was printed on 3M™High Definition License Plate Sheeting Series 6700 by 3M™ PrecisionPlate System, using 3M™ UV Curable Inkjet Ink Series 1500 with black,cyan, magenta, and yellow ink level as indicated. The square pattern canbe non-printed, i.e., no black, cyan, magenta, or yellow; printed with“processed” black, i.e., no black, full cyan, magenta, and yellow; orprinted with “true” black, i.e., full black, cyan, magenta, and yellow.The printed samples were laminated with 3M™ Digital License Plate ClearProtective Film Series 9097. The white mirror film was optionally placedon top of the laminate to form the example optical tags. Theretroreflective spectrum of the example optical tags on the printed areawas measured by an Ocean Optics Spectrometer (model numberFLAME-S-VIS-NIR), light source (model HL-2000-FHSA), and reflectanceprobe (model QR400-7-VIS-BX) over a geometry of 0.2 degree observationangle and 0 degree entrance angle, as shown by percent of reflectivity(R %) over a wavelength range of 400 nanometer to 1000 nanometer.

FIG. 13A shows the retroreflective spectra of the example optical tagsin the absence of the white mirror film, and FIG. 13B is theretroreflective spectra of the example optical tags in the presence ofthe white mirror film.

FIG. 14 depicts the contrast ratio of indicated example optical tagsbased on the R % at 950 nanometer wavelength, calculated as the ratio ofthe difference between the printed area and the non-printed area againstthe non-printed area. Because the cyan, magenta, and yellow inks havehigh transmission in near-IR region, while the black ink has lowtransmission in near IR region, the “true” black square has a muchhigher contrast ratio at near-IR wavelength 950 nanometer over thenon-printed area, compared with the contrast ratio of the “processed”black square over the non-printed area. While the black squares on theexample optical tags in the absence of the white mirror film are visibleto naked eyes, the black squares on the example optical tags in thepresence of the white mirror film are hidden from observers and thuspotentially less distracting to workers. At the same time, the contrastratio between printed area and the non-printed area are the same in theabsence and in the presence of the white mirror film, thus enablingsimilar near-IR readability.

It will be appreciated that numerous and varied other arrangements maybe readily devised by those skilled in the art without departing fromthe spirit and scope of the invention as claimed. For example, each ofthe communication modules in the various devices described throughoutmay be enabled to communicate as part of a larger network or with otherdevices to allow for a more intelligent infrastructure. Informationgathered by various sensors may be combined with information from othersources, such as information captured through a video feed of a workspace or an equipment maintenance space. In some instances, a portalconfiguration may be used such that if any of the systems describedherein detect that a user or worker has exceeded a given threshold(whether high or low), the worker is prevented from physically gainingaccess to a particular work space or other area. Information gathered bythe systems described herein can be used for further data analytics todetermine compliance with various rules or regulations, and to improvesafety processes. In some instances, a geo-location device, such as aglobal positioning system (GPS) may be incorporated into any of thesystems described herein to provide user location. In some instances,the information collected by the systems and sensors described hereinmay be used to determine remaining service life of any PPE.

It will be appreciated that based on the above description, aspects ofthe disclosure include methods and systems for determining time of use(wear time) of articles, such as PPE articles, by determining if theysatisfy at least one criterion.

Although the methods and systems of the present disclosure have beendescribed with reference to specific exemplary embodiments, those ofordinary skill in the art will readily appreciate that changes andmodifications may be made thereto without departing from the spirit andscope of the present disclosure.

In the present detailed description of the preferred embodiments,reference is made to the accompanying drawings, which illustratespecific embodiments in which the invention may be practiced. Theillustrated embodiments are not intended to be exhaustive of allembodiments according to the invention. It is to be understood thatother embodiments may be utilized and structural or logical changes maybe made without departing from the scope of the present invention. Thefollowing detailed description, therefore, is not to be taken in alimiting sense, and the scope of the present invention is defined by theappended claims.

Unless otherwise indicated, all numbers expressing feature sizes,amounts, and physical properties used in the specification and claimsare to be understood as being modified in all instances by the term“about.” Accordingly, unless indicated to the contrary, the numericalparameters set forth in the foregoing specification and attached claimsare approximations that can vary depending upon the desired propertiessought to be obtained by those skilled in the art utilizing theteachings disclosed herein.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” encompass embodiments having pluralreferents, unless the content clearly dictates otherwise. As used inthis specification and the appended claims, the term “or” is generallyemployed in its sense including “and/or” unless the content clearlydictates otherwise.

Spatially related terms, including but not limited to, “proximate,”“distal,” “lower,” “upper,” “beneath,” “below,” “above,” and “on top,”if used herein, are utilized for ease of description to describe spatialrelationships of an element(s) to another. Such spatially related termsencompass different orientations of the device in use or operation inaddition to the particular orientations depicted in the figures anddescribed herein. For example, if an object depicted in the figures isturned over or flipped over, portions previously described as below orbeneath other elements would then be above or on top of those otherelements.

As used herein, when an element, component, or layer for example isdescribed as forming a “coincident interface” with, or being “on,”“connected to,” “coupled with,” “stacked on” or “in contact with”another element, component, or layer, it can be directly on, directlyconnected to, directly coupled with, directly stacked on, in directcontact with, or intervening elements, components or layers may be on,connected, coupled or in contact with the particular element, component,or layer, for example. When an element, component, or layer for exampleis referred to as being “directly on,” “directly connected to,”“directly coupled with,” or “directly in contact with” another element,there are no intervening elements, components or layers for example. Thetechniques of this disclosure may be implemented in a wide variety ofcomputer devices, such as servers, laptop computers, desktop computers,notebook computers, tablet computers, hand-held computers, smart phones,and the like. Any components, modules or units have been described toemphasize functional aspects and do not necessarily require realizationby different hardware units. The techniques described herein may also beimplemented in hardware, software, firmware, or any combination thereofΔny features described as modules, units or components may beimplemented together in an integrated logic device or separately asdiscrete but interoperable logic devices. In some cases, variousfeatures may be implemented as an integrated circuit device, such as anintegrated circuit chip or chipset. Additionally, although a number ofdistinct modules have been described throughout this description, manyof which perform unique functions, all the functions of all of themodules may be combined into a single module, or even split into furtheradditional modules. The modules described herein are only exemplary andhave been described as such for better ease of understanding.

If implemented in software, the techniques may be realized at least inpart by a computer-readable medium comprising instructions that, whenexecuted in a processor, performs one or more of the methods describedabove. The computer-readable medium may comprise a tangiblecomputer-readable storage medium and may form part of a computer programproduct, which may include packaging materials. The computer-readablestorage medium may comprise random access memory (RAM) such assynchronous dynamic random access memory (SDRAM), read-only memory(ROM), non-volatile random access memory (NVRAM), electrically erasableprogrammable read-only memory (EEPROM), FLASH memory, magnetic oroptical data storage media, and the like. The computer-readable storagemedium may also comprise a non-volatile storage device, such as ahard-disk, magnetic tape, a compact disk (CD), digital versatile disk(DVD), Blu-ray disk, holographic data storage media, or othernon-volatile storage device.

The term “processor,” as used herein may refer to any of the foregoingstructure or any other structure suitable for implementation of thetechniques described herein. In addition, in some aspects, thefunctionality described herein may be provided within dedicated softwaremodules or hardware modules configured for performing the techniques ofthis disclosure. Even if implemented in software, the techniques may usehardware such as a processor to execute the software, and a memory tostore the software. In any such cases, the computers described hereinmay define a specific machine that is capable of executing the specificfunctions described herein. Also, the techniques could be fullyimplemented in one or more circuits or logic elements, which could alsobe considered a processor.

What is claimed is:
 1. A system comprising: at least one image capturedevice; an article of personal protective equipment (PPE) that includesa first optical pattern embodied on a surface of the article of PPE; acomputing device communicatively coupled to the at least one imagecapture device, wherein the computing device is configured to: receive,from the at least one image capture device, one or more images thatincludes the first optical pattern and a second optical pattern;determine, based at least in part on the first optical pattern and thesecond optical pattern, a spatial relation between the first opticalpattern and the second optical pattern; identify, based at least in parton the spatial relation between the first optical pattern and the secondoptical pattern, a safety condition that corresponds at least in part tothe article of PPE; and perform at least one operation based at least inpart on the safety condition.
 2. The system of claim 1, wherein thearticle of PPE includes a first optical tag attached to the article ofPPE, wherein the first optical tag includes the first optical pattern.3. The system of claim 1, wherein to determine the spatial relationbetween the first optical pattern and the second optical pattern, thecomputing device determines a relative orientation between the firstoptical pattern and the second optical pattern.
 4. The system of claim3, wherein the relative orientation is a first relative orientation,wherein the computing device: determines a second relative orientationof the first optical pattern in relation to the second optical patternthat is required for at least one of a hazard, work environment, or workactivity; determines that the first relative orientation is differentfrom the second relative orientation; and wherein to identify the safetycondition the computing device determines the safety condition based atleast in part on the second relative orientation not being satisfied bythe first relative orientation.
 5. The system of claim 1, wherein thesecond optical pattern is not embodied on the article of PPE and is notembodied on a worker wearing the article of PPE.
 6. The system of claim1, wherein the second optical pattern is embodied on at least one of thearticle of PPE or a worker wearing the article of PPE.
 7. The system ofclaim 1, wherein to determine, based at least in part on the firstoptical pattern and the second optical pattern, the spatial relationbetween the first optical pattern and the second optical pattern, thecomputing device determines that the first optical pattern and thesecond optical pattern are each included in the image.
 8. The system ofclaim 1, wherein to determine, based at least in part on the firstoptical pattern and the second optical pattern, the spatial relationbetween the first optical pattern and the second optical pattern, thecomputing device: determines a distance between the first opticalpattern and the second optical pattern; and determines that the distancebetween the first optical pattern and the second optical patternsatisfies a threshold distance.
 9. The system of claim 1, wherein thecomputing device is attached to a worker wearing the article of PPE. 10.The system of claim 1, wherein the safety condition comprises at leastone of: a worker-down event, wherein a worker has fallen; a visor event,wherein a visor position of a respirator or welding mask does not shielda face of a worker wearing the article of PPE; a respirator protectionevent, wherein a respirator is not worn over the nose of a workerwearing the article of PPE; or a hearing protection event, whereinhearing protection is not positioned to attenuate sound for the workerwearing the article of PPE.
 11. An article of personal protectiveequipment (PPE) that includes: a first optical pattern embodied on asurface of the article of PPE; a second optical pattern embodied on thesurface of the article of PPE, wherein a spatial relation between thefirst optical pattern and the second optical pattern is indicative of anoperational status of the article of PPE.
 12. The article of PPE ofclaim 11, wherein the operational status of the article of PPE isindicated by a distance between the first optical pattern and the secondoptical pattern.
 13. The article of PPE of claim 11, wherein theoperational status of the article of PPE is indicated by a relativeorientation between the first optical pattern and the second opticalpattern.
 14. The article of PPE of claim 11, wherein the article of PPEincludes a first optical tag attached to the article of PPE andincluding the first optical pattern, and wherein the article of PPEincludes a second optical tag attached to the article of PPE andincluding the second optical pattern.
 15. The article of PPE of claim11, wherein the first optical tag comprises a layer of retroreflectivematerial with the first optical pattern embodied thereon, wherein thefirst optical tag comprises a layer of mirror film layered above thelayer of retroreflective material, and wherein the first optical tagcomprises an adhesive layer adhering the first optical tag to thearticle of PPE.
 16. A pair of optical tags comprising a first opticaltag and a second optical tag, the first optical tag having a firstoptical pattern encoding a first identifier and the second optical taghaving a second optical pattern encoding a second identifier, whereinthe first identifier and the second identifier indicate, to a personalprotective equipment (PPE) management system, that the first optical tagand the second optical tag are usable as a pair of optical tags forindicating an operational status of an article of PPE when at least thefirst optical tag is attached to the article of PPE.
 17. The pair ofoptical tags of claim 16, wherein the first identifier and the secondidentifier are the same identifier.
 18. The pair of optical tags ofclaim 16, wherein the first identifier and the second identifier aredifferent identifiers.
 19. The pair of optical tags of claim 16, whereinthe first optical tag comprises a layer of retroreflective material withthe first optical pattern embodied thereon, wherein the first opticaltag comprises a layer of mirror film layered above the layer ofretroreflective material, and wherein the first optical tag comprises anadhesive layer configured for adhering the first optical tag to thearticle of PPE.